You're in 4th grade? So basically you still have another 9 years or so of your school life and you choose to worry about love and boyfriends now? My sister is in 5th grade and if she told me that I'd tell her to focus on he education which is more important right now!
You have your whole life ahead of you, please do not worry or think you need to bag a boyfriend in order to be accepted at school or simply because you like him. Young love is not really lasting or any good! Especially at your age! The truth is that you do not know what you want, you're not even a teenager yet so you have a long way to go yet in the world of discovering what you like and dislike.
Plus you say you have one week of school left? Why can't you just meet up with him in the holidays as a friend? Don't young juniors do that anymore? I used to hang out with guys and girls back in Primary...
But seriously what's the rush? He might say yes to being with you but he won't really care I can guarantee that! He is a young boy, and you are young girl, both not ready to be in a relationship, you should remain friends because if you do ask him out and he says yes and some months down the line he may end it with you (either he gets bored or something) when you're older, maybe in your teenage years, you will find it extremely difficult to talk to this guy ever again! So I say you wait till you get older, maybe when you both leave for Junior school you could get his number and start meeting with him and who knows he may like you afterwards?
But apart from them, focus on what is in the present, your education! You can't afford to mess it up, (well you can but it's not pleasant re-doing a whole year after you fail!). Guys will always be around for years to come, go out there and enjoy your youth while it lasts! Good Luck!