Yeah XD I asked the same question a while ago except can a sophomore date a senior. My main concern was that he was going to graduate so I didn't know whether it would work or not. But you can for sure.
Well yes, if you want to. It might not be the best idea. They will graduate first, they will turn 18 first and people will judge you I'm guessing. If you REALLY think something's there between you, you should go for it! Good luck!