Up until 10th grade, that was basically me as well. It took one teacher to change that, and it was because he recognized that no 2 people learn the same. Mr. Shipley. He changed my life, and entirely because he didn't do things the way 90% of teachers do them.
I am a ritalin kid, and ADD/ADHD weren't very well understood in those early days. People just assumed we were too hyper and unfocused so they tried to drug us into normal people. Nobody understood that it's more of a learning disability, just like Dyslexia, than just people being hyper. It falls under the blanket term of "Neuro-Divergent" now as there has been a couple of decades of research to better understand it. Our brains are "wired" differently, and much like a Dyslexic person or even people on the spectrum of Autism, we aren't less intelligent than a neuro-typical (normal) person, but we have to learn in a different way and some tasks we struggle with that others find easy while simultaneously finding some tasks that others find difficult to be a walk in the park. A great example of this is with Math. ADD/ADHD and word problems are like oil and water, and I really struggle with them. It's a flood of information with no structure, and my mind short circuits. On that same note, I memorized every equation within a minute or two of being introduced, and could apply them on the spot.
People with ADHD, for example, make excellent air traffic controllers. That same inability for them to focus completely on one task also gives them an incredible ability to mostly focus on several tasks, which is literally what ATC's do all day.
GW's spelling problem, especially the inconsistency, is a big red flag for Dyslexia. That doesn't mean he is dumb, far from it. We have all seen his intelligence first hand. It's no different than a person that stutters. Heck, some of the most intelligent people to have ever lived were likely on the spectrum or had other "disabilities" that we now have names for today.