About the Blackberry Bold and Wifi….?

Okay, so, I am planning to get the Blackberry Bold! But yeah, my parents said sure as long as the phone is under $ 200 which it is with all the rebates and contract. They dont want to pay an extra $30 a month though for the data plan! I was thinking, since Blackberry Bold had that Wifi thinger, can't I just use my school's internet signal to get on the web? CAN'T I? OR, do we HAVE to pay that $30, because for the iPhone I know its mandatory? Any answers? Thanks...!