diff --git a/scripts/github-repos/Gemfile b/scripts/github-repos/Gemfile
index 680c7cf..92aa6ae 100644
--- a/scripts/github-repos/Gemfile
+++ b/scripts/github-repos/Gemfile
@@ -1,7 +1,7 @@
 source 'https://rubygems.org'
 
-ruby '3.2.2'
+ruby '< 3.0'
 
 gem 'octokit'
 gem 'csv'
-gem 'yaml'
+gem 'tqdm'
diff --git a/scripts/github-repos/Gemfile.lock b/scripts/github-repos/Gemfile.lock
index a0cb690..8a5cbcd 100644
--- a/scripts/github-repos/Gemfile.lock
+++ b/scripts/github-repos/Gemfile.lock
@@ -1,33 +1,35 @@
-GEM
-  remote: https://rubygems.org/
-  specs:
-    addressable (2.8.4)
-      public_suffix (>= 2.0.2, < 6.0)
-    csv (3.2.6)
-    faraday (2.7.5)
-      faraday-net_http (>= 2.0, < 3.1)
-      ruby2_keywords (>= 0.0.4)
-    faraday-net_http (3.0.2)
-    octokit (6.1.1)
-      faraday (>= 1, < 3)
-      sawyer (~> 0.9)
-    public_suffix (5.0.1)
-    ruby2_keywords (0.0.5)
-    sawyer (0.9.2)
-      addressable (>= 2.3.5)
-      faraday (>= 0.17.3, < 3)
-    yaml (0.2.1)
-
-PLATFORMS
-  x86_64-linux
-
-DEPENDENCIES
-  csv
-  octokit
-  yaml
-
-RUBY VERSION
-   ruby 3.2.2p53
-
-BUNDLED WITH
-   2.4.13
+GEM
+  remote: https://rubygems.org/
+  specs:
+    addressable (2.8.5)
+      public_suffix (>= 2.0.2, < 6.0)
+    base64 (0.1.1)
+    csv (3.2.7)
+    faraday (2.7.11)
+      base64
+      faraday-net_http (>= 2.0, < 3.1)
+      ruby2_keywords (>= 0.0.4)
+    faraday-net_http (3.0.2)
+    octokit (4.25.1)
+      faraday (>= 1, < 3)
+      sawyer (~> 0.9)
+    public_suffix (5.0.3)
+    ruby2_keywords (0.0.5)
+    sawyer (0.9.2)
+      addressable (>= 2.3.5)
+      faraday (>= 0.17.3, < 3)
+    tqdm (0.4.1)
+
+PLATFORMS
+  arm64-darwin-22
+
+DEPENDENCIES
+  csv
+  octokit
+  tqdm
+
+RUBY VERSION
+   ruby 2.6.10p210
+
+BUNDLED WITH
+   2.4.19
diff --git a/scripts/github-repos/README.md b/scripts/github-repos/README.md
index 3210ded..98af182 100644
--- a/scripts/github-repos/README.md
+++ b/scripts/github-repos/README.md
@@ -1,56 +1,144 @@
-# Bulk creation/deletion of many repos and cs169a-team
+# Bulk creation/deletion of many repos and student teams
 
 ```
-Usage: ./github-repos.rb [required options] [invite|repos|remove|remove_access]
+Usage: ./github-repos.rb [required options] [invite|create_groups|indiv_repos|group_repos|remove_indiv_repos|remove_group_repos|remove_teams|remove_group_repos_access] [optional options]
 
 GITHUB_ORG_API_KEY for the org must be set as an environment variable.
 
-'invite' invites students provided in .csv file and creates teams, 'repos' creates team repos, 'remove' remove students, repos, teams from the org
-
 It's safe to run multiple times.
 
-Required arguments:
-    -c, --csv=CSVFILE                CSV file containing at least "Team" and "Email" named columns
-    -o, --orgname=ORGNAME            The name of the org eg org_name
-    -f, --filename=FILENAME          The base filename for repos, eg "fa23-actionmap-04", actionmap is the base file name of the repo
-    -p, --prefix=PREFIX              Semester prefix, eg "fa23" create a repos prefix, "fa23-actionmap-04", etc.
-    -t, --template=TEMPLATE          The repo name within the org to use as template eg repo_name (Assume the repo own by org)
-    -s, --studentteam=STUDENTTEAM    The team name of all the students team
-    -g, --gsiteam=GSITEAM            The team name of all the staff team
+'invite':
+Create a team called STUDENTTEAM under the org and send invitations to students to the team.
+If STUDENTTEAM already exists, the script will resend invitation to students.
+
+If PREFIX is provided, it will assume the csv file contains "Group" column, and create groups(child teams) under 
+the STUDENTTEAM, and invites them to groups.
+
+Required options:
+    -c, --csv=CSVFILE                CSV file containing at least "Username" named columns
+    -s, --studentteam=STUDENTTEAM    The team name for students' team
+    -o, --orgname=ORGNAME            The name of the org
+
+Optional options:
+    -p, --prefix=PREFIX              Semester prefix, eg fa23. If prefix is not provided, it will not create groups.
+
+'create_groups'
+Assuming students are in STUDENTTEAM, create groups for students for CHIP 10.5 and add them to corresponding groups.
+
+Required options:
+    -c, --csv=CSVFILE                CSV file containing at least "Group" and "Username" named columns
+    -s, --studentteam=STUDENTTEAM    The team name for students' team
+    -p, --prefix=PREFIX              Semester prefix, eg fa23.
+    -o, --orgname=ORGNAME            The name of the org
+
+'indiv_repos'
+Create CHIPS repos for each student in STUDENTTEAM. Repos' names are form like "[PREFIX]-[username]-[ASSIGNMENT]"
+[username] stands for the GitHub username.
+
+Required options:
+    -o, --orgname=ORGNAME            The name of the org
+    -s, --studentteam=STUDENTTEAM    The team name for students' team
+    -p, --prefix=PREFIX              Semester prefix, eg fa23.
+    -t, --template=TEMPLATE          The repo name within the org to use as template
+    -g, --gsiteam=GSITEAM            The team name of staff team
+    -a, --assignment=ASSIGNMENT      The assignment name
+
+Optional options:
+    -perm, --permission=PERMISSION   The permission of the created repos, can be 'pull', 'push', or 'admin'. Default: 'push'
+    -u, --public                     A flag infering to create public repository, otherwise the new repo is private.
+
+'group_repos'
+Create repos for each group. Repos' names are form like "[PREFIX]-[ASSIGNMENT]-[GROUPNUM]"
+Make sure groups are formed before running this command.
+
+Required options:
+    -o, --orgname=ORGNAME            The name of the org
+    -p, --prefix=PREFIX              Semester prefix, eg fa23.
+    -t, --template=TEMPLATE          The repo name within the org to use as template
+    -a, --assignment=ASSIGNMENT      The assignment name. eg chip-10.5
+    -s, --studentteam=STUDENTTEAM    The team name for students' team
+    -g, --gsiteam=GSITEAM            The team name of staff team
+
+Optional options:
+    -perm, --permission=PERMISSION   The permission of the created repos, can be 'pull', 'push', or 'admin'. Default: 'push'
+    -u, --public                     A flag infering to create public repository, otherwise the new repo is private.
+
+'remove_indiv_repos'
+Delete all repos whose names are formed like "[PREFIX]-[username]-[ASSIGNMENT]".
+
+Required options:
+    -o, --orgname=ORGNAME            The name of the org
+    -p, --prefix=PREFIX              Semester prefix, eg fa23.
+    -a, --assignment=ASSIGNMENT      The assignment name. eg chip-10.5
+
+'remove_group_repos'
+Delete all repos whose names are formed like "[PREFIX]-[ASSIGNMENT]-[GROUPNUM]".
+
+Required options:
+    -o, --orgname=ORGNAME            The name of the org
+    -p, --prefix=PREFIX              Semester prefix, eg fa23.
+    -a, --assignment=ASSIGNMENT      The assignment name. eg chip-10.5
+
+'remove_teams'
+Remove all students and groups in STUDENTTEAM from the org.
+Remove STUDENTTEAM as well.
+
+Required options:
+    -o, --orgname=ORGNAME            The name of the org
+    -p, --prefix=PREFIX              Semester prefix, eg fa23.
+    -s, --studentteam=STUDENTTEAM    The team name for students' team
+
+'remove_group_repos_access'
+Remove group access to group repos that are formed like "[PREFIX]-[ASSIGNMENT]-[GROUPNUM]".
+
+Required options:
+    -o, --orgname=ORGNAME            The name of the org
+    -p, --prefix=PREFIX              Semester prefix, eg fa23.
+    -a, --assignment=ASSIGNMENT      The assignment name. eg chip-10.5 
 ```
 
-This script creates a team that include all stundents in the same semester, eg fa23. 
-Then creates different child teams for them for the chip10.5. At a minimum, 
-you need a CSV file listing all enrolled students with columns 'Email' and 'Team'.  
-The values in the Team columns should be nonnegative integers identifying teams.
+This script offer commands to manage student teams and groups, repositories.
 
 Org setting: Assume Base permissions is no permission, each students can only access their team repos.
 
 **Assumption:** You have a GITHUB ORG API key.
 
-### Create a team under the org that includes all students in the same semester
+### Create a student team under the org and send invitations to students
+
+**Use case:** Create a team called STUDENTTEAM if it don't exist, and send invitations 
+to the students in csv file. For students NOT in STUDENTTEAM, invite them to STUDENTTEAM.
+
+### Create groups for students for CHIP 10.5
+
+**Use case:** Create groups for students for CHIP 10.5. 
+
+### Create CHIPS repo for each student
+
+**Use case:** Create CHIP repos for each student in STUDENTTEAM.
+The repos' names are formed like  "[PREFIX]-[username]-[ASSIGNMENT]". There will 
+be only one collabrator. Give GSITEAM admin access to the created repos.
+
+### Create 10.5 repos for each group
+
+**Use case:** Each group (as identified by "Group" column in CSV file)
+gets a repo for chip 10.5.  Repos' names are formed like "[PREFIX]-[ASSIGNMENT]-[TEAMNUM]"
+Every one in the same group has write access to the repo.
+Give GSITEAM admin access to the created repos.
+
+### Remove the CHIPS repos
 
-**Use case:** Create a team called STUDENTTEAM, and send invitations 
-to the students in csv file. If STUDENTTEAM exists, delete the team and 
-create a new one. (Team repos still exist) 
-For all students NOT in that team, add/invite into that team.
+**Use case:** Delete all repos whose names are formed like "[PREFIX]-[username]-[ASSIGNMENT]".
 
-### Create 10.5 repos for each child team 
+### Remove CHIP 10.5 repos
 
-**Use case:** Each team (as identified by Team column in CSV file)
-gets a repo for chip 10.5.  Repos' names are formed
-by concatenating the prefix, base file name, and the team ID. 
-(eg "fa23-actionmap-04" for team #4) For all students on that team who do 
-NOT already have access to the repo, give them write access on the repo.
-Add all repos to the gsiteam with admin permission.
+**Use case:** Delete all repos whose names are formed like "[PREFIX]-[ASSIGNMENT]-[GROUPNUM]".
 
-### Remove all team members from students team, and delete all the repos
+### Remove all team members from students teams, then delete all teams
 
-**Use case:** Delete all repos whose name matches the "PREFIX-FILENAME-team number".
-Remove all students and subteams in STUDENTTEAM from the org.
+**Use case:** Remove all students and groups in STUDENTTEAM from the org.
 
 ### Remove student access to all the chip 10.5 repos 
 
-**Use case:** Only remove the access of students teams, repos still can be accessed by
+**Use case:** Only remove the access of students groups, repos can still be accessed by
 gsi team.
 
diff --git a/scripts/github-repos/github-repos.rb b/scripts/github-repos/github-repos.rb
index 7f258df..d01a46b 100755
--- a/scripts/github-repos/github-repos.rb
+++ b/scripts/github-repos/github-repos.rb
@@ -3,224 +3,426 @@
 require 'optparse'
 require 'octokit'
 require 'csv'
-
-ENV['GITHUB_ORG_API_KEY'] = ""
+require 'tqdm'
 
 def main()
-    puts "Script start."
-    org = OrgManager.new
-    $opts = OptionParser.new do |opt|
-        opt.banner = "Usage: #{__FILE__} [required options] [invite|repos|remove]
-    GITHUB_ORG_API_KEY for the org must be set as an environment variable.
-    'invite' invites students provided in .csv file and creates teams, 
-    'repos' creates team repos, 'remove' remove students, repos, teams from the org."
-        opt.on('-cCSVFILE', '--csv=CSVFILE', 'CSV file containing at least "Team" and "Email" named columns') do |csv|
-        org.read_teams_and_emails_from csv
-        end
-        opt.on('-oORGNAME', '--orgname=ORGNAME', 'The name of the org') do |orgname|
-        org.orgname = orgname
-        end
-        opt.on('-fFILENAME', '--filename=FILENAME', 'The base filename for repos') do |filename|
-        org.base_filename = filename
-        end
-        opt.on('-pPREFIX', '--prefix=PREFIX', 'Semester prefix, eg "fa23" create a repos prefix, "fa23-actionmap-04", etc') do |pfx|
-        org.semester = pfx
-        end
-        opt.on('-tTEMPLATE', '--template=TEMPLATE', 'The repo name within the org to use as template eg repo_name') do |template|
-        org.template = template
-        end
-        opt.on('-sSTUDENTTEAM', '--studentteam=STUDENTTEAM', 'The team name of all the students team') do |studentteam|
-        org.parentteam = studentteam
-        end
-        opt.on('-gGSITEAM', '--gsiteam=GSITEAM', 'The team name of all the staff team') do |gsiteam|
-        org.gsiteam = gsiteam
-        end
+  puts "Script start."
+  org = OrgManager.new
+  $opts = OptionParser.new do |opt|
+    opt.banner = "Usage: #{__FILE__} [required options] [invite|create_groups|indiv_repos|group_repos|
+    remove_indiv_repos|remove_group_repos|remove_groups|remove_group_repos_access] [optional options]
+    GITHUB_ORG_API_KEY for the org must be set as an environment variable."
+
+    opt.separator ""
+    opt.separator "Commands:"
+    opt.separator "    invite: Create a team called STUDENTTEAM under the org and send invitations to students to the team.
+            If STUDENTTEAM already exists, the script will resend invitation to students.
+            If PREFIX is provided, it will assume the csv file contains \"Group\" column, 
+            and create groups (child teams) under the STUDENTTEAM, and invites them to groups.\n"
+    opt.separator "    create_groups: Assuming students are in STUDENTTEAM, create groups for students for CHIP 10.5 and add them to corresponding groups.\n"
+    opt.separator "    indiv_repos: Create CHIPS repo for each stedent in STUDENTTEAM. Repos' names are form like \"[PREFIX]-[username]-[ASSIGNMENT]\"
+                [username] stands for the GitHub username.\n"
+    opt.separator "    group_repos: Create 10.5 repos for each child team. Repos' names are form like \"[PREFIX]-[ASSIGNMENT]-[GROUPNUM]\"
+                Make sure groups are formed before running this command.\n"
+    opt.separator "    remove_indiv_repos: Delete all repos whose names are formed like \"[PREFIX]-[username]-[ASSIGNMENT]\".\n"
+    opt.separator "    remove_group_repos: Delete all repos whose names are formed like \"[PREFIX]-[ASSIGNMENT]-[GROUPNUM]\".\n"
+    opt.separator "    remove_groups: Remove all students and groups in STUDENTTEAM from the org. Remove STUDENTTEAM as well.\n"
+    opt.separator "    remove_group_repos_access: Remove students access to CHIP 10.5 repos that are formed like \"[PREFIX]-[ASSIGNMENT]-[GROUPNUM]\".\n"
+    opt.separator "Options:"
+
+    opt.on('-cCSVFILE', '--csv=CSVFILE', 'CSV file containing at least "Username" named columns') do |csv|
+      org.csv = csv
+    end
+    opt.on('-oORGNAME', '--orgname=ORGNAME', 'The name of the org') do |orgname|
+      org.orgname = orgname
+    end
+    opt.on('-sSTUDENTTEAM', '--studentteam=STUDENTTEAM', 'The team name for students\' team') do |studentteam|
+      org.parentteam = studentteam
     end
-    $opts.parse!
-    command = ARGV.pop
-    case command
-    when 'invite' then org.invite
-    when 'repos' then org.create_repos 
-    when 'remove' then org.remove
-    when 'remove_access' then org.remove_access
-    else org.print_error
-    end
-    puts "Run successfully."
-    puts "Script ends."
+    opt.on('-pPREFIX', '--prefix=PREFIX', 'Semester prefix, eg fa23.') do |pfx|
+      org.semester = pfx
+    end
+    opt.on('-aASSIGNMENT', '--assignment=ASSIGNMENT', 'The assignment name. eg chip-10.5') do |assignment|
+      org.assignment = assignment
+    end
+    opt.on('-tTEMPLATE', '--template=TEMPLATE', 'The repo name within the org to use as template') do |template|
+      org.template = template
+    end
+    opt.on('-gGSITEAM', '--gsiteam=GSITEAM', 'The team name of staff team') do |gsiteam|
+      org.gsiteam = gsiteam
+    end
+    opt.on('-ePERMISSION', '--permission=PERMISSION', 'The permission of the created repos, can be \'pull\', \'push\', or \'admin\'. Default: \'push\'') do |permission|
+      org.permission = permission
+    end
+    opt.on('-u', '--public', 'Create public repository, otherwise the new repo is private.') do
+      org.isPublic = true
+    end
+  end
+  $opts.parse!
+  command = ARGV.pop
+  org.invoke_command command
+  puts "Run successfully."
+  puts "Script ends."
 end
 
 class OrgManager
-    attr_accessor :orgname, :base_filename, :semester, :template, :parentteam, :gsiteam
+  attr_accessor :orgname, :assignment, :semester, :template, :parentteam, :gsiteam, :csv, :users, :permission, :isPublic
 
-    def initialize
-        @orgname = nil
-        @base_filename = nil
-        @semester = nil
-        @template = nil
-        @childteams = Hash.new { |hash, key| hash[key] = [] } # teamID => [email1, email2, ...]
-        print_error("GITHUB_ORG_API_KEY not defined in environment") unless (@key = ENV['GITHUB_ORG_API_KEY'])
-        @client = Octokit::Client.new(access_token: @key)
-    end
+  def initialize
+    @orgname = nil
+    @assignment = nil
+    @semester = nil
+    @template = nil
+    @csv = nil
+    @isPublic = false
+    @permission = 'push'
+    @users = []
+    @childteams = Hash.new { |hash, key| hash[key] = [] } # teamID => [email1, email2, ...]
+    print_error("GITHUB_ORG_API_KEY not defined in environment") unless (@key = ENV['GITHUB_ORG_API_KEY'])
+    @client = Octokit::Client.new(access_token: @key, scopes: ['user'])
+    @client.auto_paginate = true # auto pagination on
+  end
 
-    private
+  private
 
-    def gsiteam_valid?
-        gsiteam_obj = nil
-        if !@gsiteam.nil? && @gsiteam.length > 0 
-            begin
-                gsiteam_obj = @client.team_by_name(@orgname, @gsiteam)
-            rescue Octokit::NotFound
-            end
-        end
-        !gsiteam_obj.nil?
+  def read_users_from csv
+    data = CSV.parse(IO.read(csv), headers: true)
+    hash = data.first.to_h
+    print_error "Need at least 'Username' (str) columns in #{csv}" unless
+      hash.has_key?('Username')
+    data.each do |row|
+      @users << row['Username']
     end
+  end
 
-    public
+  def read_groups_and_users_from csv
+    data = CSV.parse(IO.read(csv), headers: true)
+    hash = data.first.to_h
+    print_error "Need at least 'Group' (int) and 'Username' (str) columns in #{csv}" unless
+      hash.has_key?('Group') && hash.has_key?('Username')
+    data.each do |row|
+      username = row['Username']
+      @childteams[row['Group']] << username
+    end
+  end
+
+  def to_slug(input)
+    # Convert to lowercase
+    slug = input.downcase
+
+    # Replace characters other than 0-9, a-z, '.', '_', and '-'
+    slug.gsub!(/[^0-9a-z.\-_]+/, '-')
+
+    # Remove leading and trailing hyphens
+    slug.gsub!(/^-+/, '')
+    slug.gsub!(/-+$/, '')
+
+    # Limit the string to 63 characters
+    slug = slug[0, 63]
+
+    return slug
+  end
 
-    def valid?
-        @orgname && @base_filename && @semester && @childteams.length > 0 && @template && @parentteam && gsiteam_valid?
+  def invite_valid?
+    if @orgname.nil? || @orgname.empty? || @csv.nil? || @parentteam.nil? || @parentteam.empty?
+      return false
     end
+    # process the csv file
+    if @semester.nil?
+      read_users_from @csv
+    else
+      read_groups_and_users_from @csv
+    end
+    true
+  end
 
-    def print_error(msg=nil)
-        STDERR.puts "Error: #{msg}" if msg
-        STDERR.puts $opts
-        exit 1
+  def create_groups_valid?
+    if @orgname.nil? || @orgname.empty? || @csv.nil? || @parentteam.nil? || @parentteam.empty? || @semester.nil?
+      return false
     end
+    read_groups_and_users_from @csv
+    true
+  end
 
-    def read_teams_and_emails_from csv
-        data = CSV.parse(IO.read(csv), headers: true)
-        hash = data.first.to_h
-        print_error "Need at least 'Team' (int) and 'Email' (str) columns in #{csv}" unless
-          hash.has_key?('Team') && hash.has_key?('Email')
-        data.each do |row|
-          username = row['Email']
-          @childteams[row['Team']] << username
-        end
+  def repos_valid?
+    !(@orgname.nil? || @parentteam.nil? || @semester.nil? || @template.nil? || !gsiteam_valid? || @assignment.nil? || !(['pull', 'push', 'admin'].include? (@permission)))
+  end
+
+  def remove_valid?
+    !(@orgname.nil? || @semester.nil? || @assignment.nil?)
+  end
+  
+  def remove_groups_valid?
+    !(@orgname.nil? || @semester.nil? || @parentteam.nil?)
+  end
+
+  def gsiteam_valid?
+    gsiteam_obj = nil
+    if !@gsiteam.nil? && @gsiteam.length > 0 
+      begin
+        gsiteam_obj = @client.team_by_name(@orgname, to_slug(@gsiteam))
+      rescue Octokit::NotFound
+        print_error "Can't find the gsi team in the org."
+      end
     end
+    !gsiteam_obj.nil?
+  end
+
+  public
 
-    def invite
-        print_error "csv file, base filename, template repo name, semester prefix, students team name, and gsi team name needed." unless valid?
-        first_child_team_name = %Q{#{@semester}-#{@childteams.keys[0]}}
+  def invoke_command command
+    command = command.to_sym
+    if respond_to? command
+      send(command)
+    else
+      print_error
+    end
+  end
 
+  def print_error(msg=nil)
+    STDERR.puts "Error: #{msg}" if msg
+    STDERR.puts $opts
+    exit 1
+  end
+
+  def invite
+    print_error "csv file, organization name, student team name are needed." unless invite_valid?
+    # Looking for the STUDENTTEAM in the org, see if it is exist.
+    begin
+      parentteam_id = @client.team_by_name(@orgname, to_slug(@parentteam))['id']
+    rescue Octokit::NotFound
+      parentteam_id = @client.create_team(@orgname, {name: @parentteam, privacy: 'closed'})['id']
+    end
+    if @semester.nil? 
+      # Semester prefix is not provided
+
+      @users.tqdm.each do |username|
+        begin 
+          @client.put(%Q{/orgs/#{@orgname}/teams/#{to_slug(@parentteam)}/memberships/#{username}})
+        rescue Octokit::Forbidden
+          print_error "Can't invite or add students if team synchronization is set up"
+        rescue Octokit::UnprocessableEntity
+          print_error "Incorrect GitHub username (An org name provided)"
+        end
+      end
+    else
+      # Semester prefix is provied
+      # create groups and invite students to the groups
+      @childteams.tqdm.each_key do |team|
+        childteam_name = %Q{#{@semester}-#{team}}
         begin
-            parentteam_obj = @client.team_by_name(@orgname, @parentteam)
+          childteam = @client.team_by_name(@orgname, to_slug(childteam_name))
         rescue Octokit::NotFound
-            parentteam_obj = nil
+          childteam = @client.create_team(@orgname, {name: %Q{#{@semester}-#{team}}, parent_team_id: parentteam_id})
+        end
+        childteam_id = childteam['id']
+        @childteams[team].tqdm.each do |member|
+          # Try no check invitations before create one.
+          # send invitation
+          begin
+            @client.put(%Q{/orgs/#{@orgname}/teams/#{childteam.slug}/memberships/#{member}})
+          rescue Octokit::Forbidden
+            print_error "Can't invite or add students if team synchronization is set up"
+          rescue Octokit::UnprocessableEntity
+            print_error "Incorrect GitHub username (An org name provided)"
+          end
         end
+      end
+
+    end
+  end
+
+  def create_groups
+    print_error "csv file, students team name, semester prefix, org name are needed." unless create_groups_valid?
+
+    # Looking for the STUDENTTEAM in the org, see if it is exist.
+    begin
+      parentteam_id = @client.team_by_name(@orgname, to_slug(@parentteam))['id']
+    rescue Octokit::NotFound
+      print_error "Please make sure the invite command runs first, or students team is created."
+    end
+
+    failed_username = []
 
+    # create groups and add students to their groups
+    @childteams.tqdm.each_key do |team|
+      childteam_name = %Q{#{@semester}-#{team}}
+      begin
+        childteam = @client.team_by_name(@orgname, to_slug(childteam_name))
+      rescue Octokit::NotFound
+        childteam = @client.create_team(@orgname, {name: %Q{#{@semester}-#{team}}, parent_team_id: parentteam_id})
+      end
+      childteam_id = childteam['id']
+      @childteams[team].tqdm.each do |username|
         begin
-            if parentteam_obj
-                @client.team_by_name(@orgname, first_child_team_name)
-                parentteam_id = parentteam_obj['id']
-            else
-                parentteam_id = @client.create_team(@orgname, {name: @parentteam, privacy: 'closed'})['id']
-            end
-        rescue Octokit::NotFound
-            # students team exists before invite
-            # remove all members in this team, and delete the team.
-            parentteam_id = parentteam_obj['id']
-            old_team_members = @client.team_members(parentteam_id)
-            old_team_members.each do |member|
-                if @client.organization_membership(@orgname, :user => member['login'])['role'] == 'member'
-                    @client.remove_organization_member(@orgname, member['login'])
-                end
-            end
-            @client.delete_team parentteam_id
-            parentteam_id = @client.create_team(@orgname, {name: @parentteam, privacy: 'closed'})['id']
+          @client.add_team_member(childteam_id, username)
+        rescue Octokit::UnprocessableEntity
+          # save the incorrect username
+          failed_username << username
         end
+      end
+    end
 
-        @childteams.each_key do |team|
-            childteam_name = %Q{#{@semester}-#{team}}
-            begin
-                childteam = @client.team_by_name(@orgname, childteam_name)
-            rescue Octokit::NotFound
-                childteam = @client.create_team(@orgname, {name: %Q{#{@semester}-#{team}}, parent_team_id: parentteam_id})
-            end
-            childteam_id = childteam['id']
-            @childteams[team].each do |member|
-                if !@client.team_invitations(childteam_id).any? {|invitations| invitations.email == member}
-                    # send invitation
-                    begin
-                        @client.post(%Q{/orgs/#{@orgname}/invitations}, {org: @orgname, email: member, role: 'direct_member', team_ids: [childteam_id]})
-                    rescue Octokit::UnprocessableEntity
-                        # member is already a part of org
-                        next
-                    end
-                end
-            end
+    # print the usernames that is failed to add to groups
+    if !failed_username.empty?
+      puts 'Failed to add these usernames to groups:'
+      puts failed_username
+    end
+  end
+
+  def indiv_repos
+    print_error "Missing required options or invalid options." unless repos_valid?
+    
+    # Looking for the STUDENTTEAM in the org, see if it is exist.
+    begin
+      parentteam_id = @client.team_by_name(@orgname, to_slug(@parentteam))['id']
+    rescue Octokit::NotFound
+      print_error "Please make sure students team is created."
+    end
+
+    gsiteam_id =  @client.team_by_name(@orgname, to_slug(@gsiteam)).id
+    self_user_name = @client.user.login
+
+    # create individual repos and give each student in the student team write access to the repos
+    @client.team_members(parentteam_id).tqdm.each do |mem|
+      if self_user_name != mem.login
+        new_repo_name = %Q{#{@semester}-#{mem.login}-#{@assignment}}
+        if !@client.repository? %Q{#{@orgname}/#{new_repo_name}}
+          begin
+            new_repo = @client.create_repository_from_template(%Q{#{@orgname}/#{@template}}, new_repo_name, 
+              {owner: @orgname, private: !@isPublic})
+          rescue Octokit::NotFound
+            print_error "Template not found."
+          end
+        else
+          new_repo = @client.repo(%Q{#{@orgname}/#{new_repo_name}})
+          @client.update_repository(new_repo.full_name, { private: !@isPublic })
         end
+        @client.add_collab(new_repo['full_name'], mem.login, permission: @permission)
+        @client.add_team_repository(gsiteam_id, new_repo['full_name'], {permission: 'admin'})
+      end
     end
 
-    def create_repos
-        print_error "csv file, base filename, template repo name, semester prefix, students team name, and gsi team name needed." unless valid?
-        @childteams.each_key do |team|
+    # create individual repos and give each student in each group write access to the repos
+    @client.child_teams(parentteam_id).tqdm.each do |childteam|
+      @client.team_members(childteam.id).each do |mem|
+        if !mem.login.nil? && self_user_name != mem.login
+          new_repo_name = %Q{#{@semester}-#{mem.login}-#{@assignment}}
+          if !@client.repository? %Q{#{@orgname}/#{new_repo_name}}
             begin
-                team_id = @client.team_by_name(@orgname, %Q{#{@semester}-#{team}})['id']
+              new_repo = @client.create_repository_from_template(%Q{#{@orgname}/#{@template}}, new_repo_name, 
+                {owner: @orgname, private: !@isPublic})
             rescue Octokit::NotFound
-                print_error "Students teams information mismatched."
-            end
-            gsiteam_id = @client.team_by_name(@orgname, @gsiteam)['id']
-            new_repo_name = %Q{#{@semester}-#{@base_filename}-#{team}}
-            if !@client.repository? %Q{#{@orgname}/#{new_repo_name}}
-                begin
-                    new_repo = @client.create_repository_from_template(%Q{#{@orgname}/#{@template}}, new_repo_name, 
-                        {owner: @orgname, private: true})
-                rescue Octokit::NotFound
-                    print_error "Template not found."
-                end
-                @client.add_team_repository(team_id, new_repo['full_name'], {permission: 'push'})
-                @client.add_team_repository(gsiteam_id, new_repo['full_name'], {permission: 'admin'})
+              print_error "Template not found."
             end
+          else
+            new_repo = @client.repo(%Q{#{@orgname}/#{new_repo_name}})
+            @client.update_repository(new_repo.full_name, { private: !@isPublic })
+          end
+          @client.add_collab(new_repo['full_name'], mem.login, permission: @permission)
+          @client.add_team_repository(gsiteam_id, new_repo['full_name'], {permission: 'admin'})
         end
+      end
     end
+  end
 
-    def remove
-        print_error "csv file, base filename, template repo name, semester prefix, students team name, and gsi team name needed." unless valid?
-        # remove and delete all repos from the students team, delete all child teams
-        # also cancel all pending invitaions
-        @childteams.each_key do |team|
-            repo_name = %Q{#{@orgname}/#{@semester}-#{@base_filename}-#{team}}
-            @client.delete_repository(repo_name)
-            begin
-                childteam_id = @client.team_by_name(@orgname, %Q{#{@semester}-#{team}})['id'] # eg slug fa23-01
-            rescue Octokit::NotFound
-                next
-            end
+  def group_repos
+    print_error "Missing required options or invalid options." unless repos_valid?
 
-            # remove students from the student teams
-            team_members = @client.team_members(childteam_id)
-            team_members.each do |member|
-                if @client.organization_membership(@orgname, :user => member['login'])['role'] == 'member'
-                    @client.remove_organization_member(@orgname, member['login'])
-                end
-            end
+    child_teams = @client.child_teams(@client.team_by_name(@orgname, to_slug(@parentteam)).id)
+    gsiteam_id = @client.team_by_name(@orgname, to_slug(@gsiteam))['id']
 
-            @client.team_invitations(childteam_id).each do |invitation|
-                # cancel all pending invitations
-                @client.delete(%Q{/orgs/#{@orgname}/invitations/#{invitation[:id]}})
-            end
-            @client.delete_team childteam_id
-        end
-        # delete students team
+    # create tean repos and give each team a write access 
+    child_teams.tqdm.each do |team|
+      group_num = team.slug.match(/-(\d+)$/)[1]
+      new_repo_name = %Q{#{@semester}-#{@assignment}-#{group_num}}
+      if !@client.repository? %Q{#{@orgname}/#{new_repo_name}}
         begin
-            team_id = @client.team_by_name(@orgname, @parentteam)['id']
-            @client.delete_team team_id
+          new_repo = @client.create_repository_from_template(%Q{#{@orgname}/#{@template}}, new_repo_name, 
+            {owner: @orgname, private: !@isPublic})
         rescue Octokit::NotFound
-            # do nothing if no such team
+          print_error "Template not found."
         end
+      else
+        new_repo = @client.repo(%Q{#{@orgname}/#{new_repo_name}})
+        @client.update_repository(new_repo.full_name, { private: !@isPublic })
+      end
+      @client.add_team_repository(team.id, new_repo['full_name'], {permission: @permission})
+      @client.add_team_repository(gsiteam_id, new_repo['full_name'], {permission: 'admin'})
     end
-    
-    def remove_access
-        @childteams.each_key do |team|
-            repo_name = %Q{#{@orgname}/#{@semester}-#{@base_filename}-#{team}}
-            begin
-                childteam_id = @client.team_by_name(@orgname, %Q{#{@semester}-#{team}})['id'] # eg slug fa23-1
-            rescue Octokit::NotFound
-                next
-            end
-            @client.remove_team_repository(childteam_id, repo_name)
+
+  end
+
+  def remove_indiv_repos
+    print_error "org name, assignment name, semester prefix are needed." unless remove_valid?
+
+    repos = @client.org_repos(@orgname)
+    repos.tqdm.each do |repo|
+      if repo.name =~ /^#{Regexp.escape(@semester)}-(.*)-#{Regexp.escape(@assignment)}$/
+        @client.delete_repository(repo.full_name)
+      end
+    end
+  end
+
+  def remove_group_repos
+    print_error "org name, assignment name, semester prefix are needed." unless remove_valid?
+
+    repos = @client.org_repos(@orgname)
+    repos.tqdm.each do |repo|
+      if repo.name =~ /^#{Regexp.escape(@semester)}-#{Regexp.escape(@assignment)}-\d+$/
+        @client.delete_repository(repo.full_name)
+      end
+    end
+  end
+
+  def remove_groups
+    print_error "org name, semester prefix, students team name are needed." unless remove_groups_valid?
+
+    # Looking for the STUDENTTEAM in the org, see if it is exist.
+    begin
+      parentteam_id = @client.team_by_name(@orgname, to_slug(@parentteam))['id']
+    rescue Octokit::NotFound
+      print_error "Please make sure students team is created."
+    end
+
+    # Remove students in the students team from org
+    self_user_name = @client.user.login
+    @client.team_members(parentteam_id).tqdm.each do |mem|
+      if !mem.login.nil? && mem.login != self_user_name
+        @client.remove_organization_member(@orgname, mem.login)
+      end 
+    end
+
+    # Remove students in each group
+    @client.child_teams(parentteam_id).tqdm.each do |childteam|
+      @client.team_members(childteam.id).each do |mem|
+        if !mem.login.nil? && mem.login != self_user_name
+          @client.remove_organization_member(@orgname, mem.login)
+        end
+      end
+    end
+
+    # Remove students team, groups will be removed as well
+    @client.delete_team parentteam_id
+  end
+
+  def remove_group_repos_access
+    print_error "org name, assignment name, semester prefix are needed." unless remove_valid?
+
+    repos = @client.org_repos(@orgname)
+    repos.tqdm.each do |repo|
+      match = repo.name.match(/^#{Regexp.escape(@semester)}-#{Regexp.escape(@assignment)}-(\d+)$/)
+      if match
+        group_num = match[1]
+        begin
+          childteam_id = @client.team_by_name(@orgname, to_slug(%Q{#{@semester}-#{group_num}}))['id'] # eg slug fa23-1
+        rescue Octokit::NotFound
+          next
         end
+        @client.remove_team_repository(childteam_id, repo.full_name)
+      end
     end
+  end
 end
 
 main
\ No newline at end of file
diff --git a/scripts/github-repos/team-test.csv b/scripts/github-repos/team-test.csv
new file mode 100644
index 0000000..3472ea9
--- /dev/null
+++ b/scripts/github-repos/team-test.csv
@@ -0,0 +1,3 @@
+Group,Username,Name
+1,KCsama,Amy
+2,Gangster-Who,Gang
\ No newline at end of file