I would NOT RECOMMEND this. Yes, it would be fun, but the confiscation of an expensive toy is not.
Personally, I do not use a laser in any area that is full of people.
Any attention is unwanted attention.
Kids will want to try it out and tell you to burn teachers or point it in someones eyes and you can end up in a LOT of trouble.
These things are not allowed in a school environment. Toting a high power laser in a public place is a bad idea.
The only lasers I use in public are my 808nm pens. They are easy to conceal and do not draw attention. It is completely inconspicuous and cool to show off (to limited amounts of people) at the same time- although, I would not recommend bringing one of these to school either.
High school kids and potentially hazardous "toys" do not mix.
Please use responsibly. For the sake of the hobby.