Simple Mic System

I am a novice when it comes to sound but I do understand the basics. I am at a school without an auditorium and would like to have a simple and easy solution for my middle school students to be able to be heard. I want 6-8 lapel or lavalier mics. I would like it to be fairly inexpensive and I realize the quality won't be as great and I am okay with that as long as it doesn't make the production worse. Any suggestions on what type of mic system I can look into? Again, this has to be somewhat portable and needs to be wireless and attached to body - but we do not have a stage so I don't want to spend a great deal on something that isn't permanent.