I just got my private pilot certificate back in July. I started in October of 2017. I used Brennan Miller at Brazos Valley Flight Services. BVFS is located near the general aviation terminal at Easterwood. Great company and they do their best to instruct to the student's ability and skill level. They also use an easy scheduling service. A discovery flight is $90.
I can't say anything opinionated about the Texas Flying Club at Coulter airfield. However, I have never heard anything negative about them.
Best of luck to your son. It's a wonderful hobby/career interest.
Noblemen fight to the end. Victory or Death.