Should I confess to my crush?

so basically i'm pretty good friends with this guy from my SAT class. i met him about two or three months ago, and we ended up talking a LOT on facebook. after that, he gave me his number and email, and we chatted or texted on a daily basis, and said good night and things like that. we have really similar taste in music (we're both music lovers) and we fangirl all the time. we just get along really well and are pretty close.

and recently, over winter break, we spent about a week together (from 10am to 5pm every day) and really bonded, and we're really friendly (e.g. i rest my legs on his, play with each other's hair, share food/drinks, stare at each other).

so of course, i started to like him. and i guess a few months is kind of short, but i really like him for who he is and not just other superficial reasons. but i felt different around him, like i could be okay with either us being friends or something more; i could be happy with both. i'd never felt that way before, so i want to tell him how i feel. i wrote a letter and plan to give it to him soon.

just saying, the letter is simply telling him how i feel. i'm not asking for a relationship or anything from him, i just really want to let him know how i feel about him, and our friendship. because on his tumblr, he said he doesn't like anyone, and i know that, and i'm not asking him to like me back or ask me out, just telling him how i feel, you know?

the thing is, i only see him this saturday, and then next saturday, and then SAT class is over, so i technically will never see him again (since we go to different schools) unless we meet in our own time.

do you think i should give him the letter? and if i do, when should i give it to him?