My projects are gone!

My school system changed my school google account and now when I log in with the new email, my projects are gone.

Projects are associated to e-mail. If you change your e-mail, Your projects are on the old e-mail and you cannot have it on the new e-mail.
You can recover them: Sign in with the old e-mail, then, export all your projects (.aia) and import them on new account.