Is it legal for the school to suspend me if i wasnt on school property or grounds.?

[gwynethpaltrow8]

yesturday i got out early with my friend and we got off campus passes, we walked to his house right by the school, we smoked and were walking back to my house which you have to walk in front of the school, we were walking across the street from the school when the school officer drove by and stopped us and asked what we were doing, we showed him our off campus and they still brought us into the office and they called our parents to let them know we were hanging out and my mom said to put me back in school and they searched us, i didnt have anything on me, my friend had ALOT of weed in his backpack when he got searched, i got called back in when i was walking to class, they questioned us and made us admit we were high he was threating to take me to juvu so i admitted, we then got suspended for 5 days and have to change schools, i understand it was stupid of us but in the codes it says it happend on school campus which we werent on campus, im just asking if its legal for them to do that, even thoe none of it happend of school grounds? is it still legal for them to do that?