Suddenly not hitting in baseball?

I was a late starter in baseball, I started when I was 11 (I'm 14 now) my first year of little league was awful. The next year I hit a growth spurt, went to some camps and hitting instructors and I hit about .600 hit a double or triple almost every game and had one homer. The next year on the big diamond I hit around .300 which is somewhat below average for my league, then that year in fall ball I only hit about .250 not to mention the pitchers weren't even good. Now I'm playing for my JV team as a freshman and I'm currently without a hit, people tell me my swing looks great, I hit off the tee every day, and I watch the ball, I'm just not making good contact, weak grounders, choppers, infield flies. What can I do?