Ratatype is a free online typing tutor and test.
Don’t get to excited about the free test on the front page. You type one line and it tells you your speed and then directs you to sign up.
Unfortunately, if Facebook is blocked at your school, then students will be required to create yet another account. Ratatype doesn’t support any other service for authentication besides Facebook. Once you are signed up, you can go through the tutor and use the typing test to get certified.
Teachers can create groups for each of their classes and allows the teacher to monitor the student’s progress.
Ratatype is a free service, and if you are looking at keyboarding curriculum in your school, would be something to investigate.