(New teacher portal - member.koobits.com)
Teacher can set whether a student can access to Brain Games by selecting "Manage Class" on the top > select Class > select student(s) to tick or untick access to Brain Games.
(Old teacher portal - https://problemsums.koobits.com/)
Teacher can control student's access to Brain Games in its student account.
Once linked, click Activities from top navigation menu to see the settings.
Select your class, and tick the 'Allow access' option besides each student's name to allow access, or deselect it to block the student's access. Then click 'Save' to confirm.