ALso suggest me How I can do :
Student A will need to cache a chemistry topic unit at (https://site.com/chemistry/) which is start page 1. Student A visits that chemistry page link (set in the manifest as start page 1), adds the chemistry icon (assigned to start page 1) from the “add to home screen” pop up, and can now study (https://site.com/chemistry/) offline as needed. Student B would follow the same process to a biology page (https://site.com/biology/) set in the manifest as start page 2, adds the biology icon (assigned to start page 2) from the add to home screen pop up, and studies that unit off line as required. And so on for each student.