Is there any way an iPhone can be unlocked without knowing the passcode?

My principal took my phone and demanded that I write down the passcode for it. I refused. So he said "Well, I'll keep your phone, and I'll call your mother and me and her can go through it together."

I don't think he has a right to go through my phone anyway. But, does he mean that he is planning on cracking the code or something? Can he do that? Is it possible?

btw, the passcode is pretty complicated, letters and numbers, i don't think it could be guessed.

It is not possible for especially your principal to crack the pass-code for your phone.