Welcome Nick's mom! The more experienced posters have given lots of advice, so I don't have much to add except in the form of being a baseball mom. Do not under any circumstances approach the coach regarding playing time. You will be labeled as "that mom" and it will follow your son throughout high school. He had a discussion with the coach so coach knows he's eager to earn it. Now it is up to him to prove it. He needs to have the most hustle, be the first one there, be the one racing after foul balls down the line, etc. Also remember, he's a sophomore, so there are a lot of upper classmen that coach is more familiar with and its possible coach is giving them a chance to succeed or fail before giving away their spots.
As parents, we are now in the role of support staff. For me, at least, this means getting him where he needs to go, making sure uniform is clean (we've had great conversations while standing over the sink with bars of Fels Napha soap and white pants...he helps because I am definitely not doing the 50s housewife thing!), listen when he needs to vent, provide constructive feedback if needed, and kick his butt a little if needed. There is no bashing of teammates allowed. I cannot stress this enough! These are his teammates and like family. I would never put down one of my children in order to make the other feel better, so why would it be ok with teammates? No talking negative about coaches.
I believe Chicagoland has better competition than my neck of the woods, but even around here, mid 70s doesn't put a pitcher in the stud category. If your son is passionate, make sure he's on the best summer team possible and go to a showcase if he hasn't already. PBR has lots of local events in Illinois that are relatively inexpensive. This will give you an accurate starting point to gauge how he stacks up regarding 60 times, arm speed, exit velo and they give a paragraph write up regarding performance. The top showcases are Perfect Game, but are much more costly and a ways away. If you can afford it, do it, but it's not an option for us at this time. The off season is where he will need to work hard regarding strength so that he can show up next season and prove he's a beast. My son, packed on 15 lbs of muscle, hit the weights hard and trained like there was no tomorrow. It paid off. Notice that I said he did it. If it's their dream, they need to do it. Mom cannot be hounding them to lift or workout. The only time I am "hands on" is if he needs a cage session and dad isn't home (this is how he works through things mentally). I will sit behind the screen with my batting helmet and toss balls silently as he works through whatever is going on in that head and try not to squeal like a girl.
And remember, you need to behave and not share any of your thoughts regarding playing time with anyone in the stands. There are 40+ parents on your side alone that believe their player is the best out there
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