Not much to go on, someone already asked what your son wants, that's most important. If this is about college, I believe that there are more lax scholarships than hockey ones.
Admission deadlines vary a bit from school to school but you are a bit behind if you are looking for next year.
If his grades aren't great, get him a tutor. A good athlete is important, a good athlete and good student will open more doors.
Have him take the SSAT's as almost all schools are going to want it. Much like SAT's, consider a tutor before he takes the test.
If he has good grades and solid SSAT score, you've made the coaches life much easier.
Next put together a highlight reel, obviously mostly positive but it's not a bad idea to have a screw up or two in there. Email the coaches to let them know you are interested along with a link to his film. The film shouldn't be more than a few minutes long. If you can find an example of a mistake and then a similar play later where he does it right, you want this on the film, shows him learning.
Do some showcase tournaments. If you are looking at prep's in New England most of them attend all the area ones like HNIB, PrepShowcase, etc. Many coaches will make themselves available to talk to perspective playersparents during the event.
Google the coaches name of the schools your player is interested in and see if he works any hockey camps during the summer. If he does, sign up for the camp. This is a great chance for the coach to get to see your kid's work ethic, attitude, interaction, etc. It can backfire if your kid isn't hard working or a jerk to the other players.
Last and certainly not least, if you are looking at "name" schools like Phillips or Groton, it's not a bad idea to make sure you look through your kids social media accounts and scrub it for anything a school may not like. As one coach told my son, "You get tagged in a picture at a keg party, I'm moving on. I don't need any headaches".
This is may been the best thread on the dboard ever. Real advice and good information. Thank you!