Lots of great input here, and the good thing is you are already aware of this site and can use it to inform yourself and help your son on his journey.
Your son will change in so many ways now that he is in high school--our focus was to be sure our son had all of the opportunities to make himself a better player and get a chance to play college baseball. So we paid for the private lessons, the travel ball teams, and then the showcases, camps and college visits as he reached the decision stage. Be prepared to spend the money, but we felt it was all worth it as he focused on baseball instead of getting into time-wasting activities or trouble. He continues on learning life lessons through his college baseball experience.
Good luck and enjoy the journey--as many here will tell you, it goes really fast!