What did he mean by this? Does he care about me or is he just playing?

You both are so young and he probably was super shy when you told him you liked him. He may have a school girl crush on you but may not know how to tell you or what to do, nothing wrong with that, you are so young and the 8th grade is a major year. I cant remember anyone I know being in a relationship in the 8th grade, we all had crushes and that was about it. Just have fun, be best friends because that may be the best and healthiest type of relationship for you both especially if you want to be friends with him for a long period of time.