[AmethystDrew]

Scenario the first: Honestly, I've gone both routes, and regretted both. There's been a guy I didn't tell because I was /sure/ he was straight, and then found out later that the reason he was hanging out with me so much was because he had a crush on me (though he still identifies as straight). I've also told my best friend that I had a crush on him, and not only been very rudely rejected, but lost a good friend for about 6 months until he could come to terms with my sexuality.

Second Scenario: I'm from Canada, so I'm pretty sure that that's 11th/9th grades, right? I've known two couples that were seniors/freshmen. It depends on how you both feel about it (and, of course, each other), and you'll likely draw a few extra stares because of the age difference, but two years really is just a drop in the pond when you like someone. =]