This is a topic that will help you forever, all you kids that do illusions at school. STOP. Kids are simple minded and think they know everything at the same time so and easy way to avoid being heckled (not 100% of the time) is to do tricks to adults. Why you ask.
a) an adult will not come and just assult you( grab your deck, hand, shirt ...ect.
b) they will understand trick(99% of the time)
c) its always better the entertain someone alot older than you
d) job oportunities
and the best reason of all
f) kids get mad
Not really I think praticing in front of kids at your school is great
Yes they do try to grab your props but it so easy to fool them
And they could inv you to thier b-day party so you can do some magic for thier friends and whoever might be there so ya magic at school i think is ok