What steps should you take to protect these settings that you are a system administrator for a high school and responsible for five student computer labs and you need to prevent students from accessing the system BIOS on the machines?

It is beneficial to assign a BIOS password to all systems. Because BIOS passwords are conveniently circumvented by students with access to the machine, you should also consider locking covers or case alarms for lab systems. Expecting lab assistants to watch systems or installing security cameras would be prohibitively expensive, and the password would not necessarily be as secure. Obviously, removing the BIOS battery would have never work.