Do you have a computer? If so, I can help you, but please keep in mind that if you install Hopscotch, your school might be unhappy about that.
EDIT: You can do it using a software called “3UTools”. Download and install it on your computer, plug in your iPad, create a spare Apple ID just for installing apps using this software. I do not recommend using your main Apple ID for this (if you have one), even though the software says that it isn´t sent to Apple´s servers. After that, go to the “Apps” section (when your device is connected), log in with your Apple ID using the button “Bind”. Now, I think that you just can search up Hopscotch and click on “Download”. Tell me if it doesn´t work!