First off. Love Ace Mentoring!Use them as they should have some connections to colleges.
Adhd I know about and tough for a kid to do study for Act by himself (I assume). If you can afford it a tutor can be extremely helpful. Sometimes a few things need to be pointed out that just are not obvious.
Know kids that went from 27 to 34 but were very good at math. His math /science scores are more important then the reading /English scores for engineering. For my son math was a strength so he tried to up that since it would be easier and trust me, a tutor (not many sessions), showed him something and like his English scores took off.
If going to “try” meds do it now while he is not in school. It can take some time to adjust but some will see a difference almost right away like after a few days.
Make sure he is excersising. It helps. Biofeedback helps also FYI.
Check out Iowa State University. Great school for engineering. Helped a family with similar everything get in there. Go online and the regent application is for Iowa and Iowa State and I think one other. See where your son comes in at on their automatic point system. It’s a really good school, lots of spirit, kids love going there, decent merit depending on your score as above. Not badly priced OOS and one of the largest engineering fairs out there. Kids come out with job offers.