Im feeling really down because of something stupid?

I'm not the smartest person in my school, by far, but I've always have a good relationship with teachers and got above average grades, but when prefects were chosen I wasn't on the list (and it's like, half the school that are chosen).There are people who were chosen and they are never in school and some of the have been suspended,im not saying they dont deserve to be one,but if they are on there then why arent I?!, , and I know I shouldn't let this affect me but it does, to know that all my good behaviour and grades have gone unnoticed and unappreciated. How can I make myself feel better? They said they picked them going on who participated in the school sports clubs, I dont have time for that, I do dance everyday straight after school, then do swimming and badminton.