When my son decided not to play college ball (I documented his decision on here a few years back - It was after his Soph HS year) we started touring colleges through the normal tour and meet with an Admissions Officer thing most colleges have setup. What I can tell you is it varied from school to school as to how they viewed athletics as an admissions factor. My sons GPA was right around 3.9 unweighted and had a 30 ACT. He wanted to go to a larger state school. We toured and met with admissions consulars at schools like Iowa, Mizzou, Wisconsin, MSU (Go Green), as well as some mid sized schools (Miami-Ohio, Central Mich, etc). The majority of them saw playing sports as a plus, especially as he was able to keep his grades up while being a 3 sport athlete.
What we discovered early on is there are other things that he did, while playing sports, that set him apart. Things that we would not have thought to put on a college application or in an essay if some of the admissions consulars had not brought them up to us.
Our school district requires sports programs to have a community service component. Through that he volunteered time providing meals to under privileged folks, teaching baseball skills to the community youth, packing food for the local food pantry, collecting food for the troops, etc. As it was not a concentrated effort to startup his own charity, or a huge time commitment we initially dismissed this as being something to include on a college application.
In addition he was tapped to be a mentor to incoming freshman at his HS. Our school uses a lot of athletes in this capacity as they see them as school leaders. Again, not a huge time commitment and really part of his day to day school activities, but something that should be put on a college application.
He was nominated as JKB leader (http://www.jkbfoundation.org). He was not one of the two folks selected from our school, but it turned out this was a huge thing on his college application as just being nominated is an honor. Again, something that we did not think of originally, but it turned out it could be a difference maker.
What I am getting at, is this, your son may not have started up a charity or spent significant amount of time volunteering in the community but there are things he may have done to make a difference that you are seeing as day to day expectations/life for him. I would highly suggest taking a visit to a few of the schools on his list and meeting with the admissions consulars. Do this as a regular student, not as an athlete. They can take a look at his grades and talk to you about what he has done during HS that may make a difference in his college application.