The answer might depend on what state you're in. While I was an adult student in California I was arrested multiple times for civil disobedience at demonstrations, but I was never convicted of anything. I teach at a community college in California, and frankly it never even occurred to me when applying that I had anything to disclose. It's never been an issue. An arrest is not a criminal record. I don't remember the language on the employment application, but it probably asked about convictions, not arrests.
We had a guy who applied for a part-time teaching job at my school, and we wanted to hire him, but he had an old conviction from shooting tin cans (presumably while inebriated) out in the desert. I don't know what the actual charge was, but presumably it was a misdemeanor. We did have to go through some formalities before we could hire him. I think we had to get someone at HR to sign off and say that it was irrelevant because it was so minor and such a long time ago. We were motivated to go through that process because we already knew him well and we wanted to hire him.
My advice would be that you should absolutely not disclose this to anyone when you apply for a job, ever. Morally, you're innocent until proven guilty. Practically, there is no central database of arrests (as opposed to convictions), so they won't find out. Keep in mind that if you show the bill of rights to a sampling of Americans, roughly half will say they disagree with it. If you've ever been on a criminal jury, you've probably seen how roughly half of your fellow jurors believe that if someone has been arrested, he must have done something wrong.