@aggie82 Check out the interactive map. It’s so helpful. I just looked for your buildings and easy peasy getting to those. They are all in the same area. Profs won’t hold students over so they have the full 20 minutes. It’s longer than you think. AND if the 2nd class is a stickler on punctuality, your son can visit with the prof after first lecture and explain that he has prior class but will do his best to get there on time.
Here’s the link for map.
https://www.tamu.edu/map/index.html