Legal Question in Constitutional Law in Arizona

Honestly you would need to elaborate a little more. If your under 18 and the school function was a high school function you have substantially less protections. Second you choose to go to the school function so it's not really a seizing of your license. You could have chosen not to go in which case you never would have relinquished your license. When an officer seizes something of yours it can be done without your consent. Even if this was a college/university level function you still consented to their holding on to your license, so more likely than not there isn't much you can do. In the future you can always refuse to go to such a function. In some ways you can compare this to being searched at the airport. You can always choose not to fly and then you do not get searched.