Eli5: Would Faraday Cages block Cell Signals well enough to utilize them in a classroom setting?

Question

I.e. ‘bricking the phone’ for the students benefit

In: Engineering

Answer 1

Get administrator to agree to buy a big jar of lollipops every other month > Box on desk at front of class > Put phone in box > At end of class pick up phone and take a lollipop.