> if you had trouble in school for example that's a classic ADHD symptom

or if you excelled at some topics which you found interesting but did middlingly or poorly at others...

I watched the skepticism form then evaporate in my psychiatrist as I explained that I did relatively well in school overall... except for the three or four classes I thought were boring, and how I consistently procrastinated but managed to pull off decent work right before hand.

(I got diagnosed after 30, though apparently my elementary school wanted to screen me.)