Is my boyfriend too immature for me, should I dump him?

My mom told me I should since I'm going away to college next year and he's 17 and a junior in high school, (he's actually supposed to be a senior but he got kept back a year back in middle school) but anyway she said that when I get to college I will find him and other high school boys too immature and would want to date one of the guys at school instead so I should dump him now so he can move on but I don't want to and I see nothing wrong with him at all. But my mom is acting like it's for my own good, Should I do it?