@stuckonu  This reminds me of my son.  He was not a great student, he had untreated ADHD, my husband was totally opposed to medication.  His teachers rarely saw that he was actually fairly intelligent but he had a winning personality.  He scraped through college and is now a VP of a staffing company, a business that benefits from his personality, his street-smarts, and heck, he's developed a lot of additional intelligence now too!  My husband and I always knew if we could pull, push, drag him through school he would be a success and he is.  
My daughter is the one with very high intelligence, my son has been known to introduce her as the smartest person he knows.  She has a great personality but not his charisma and drive.  She's doing fine too though.  She had/has ADD and it still affects her.  The typical girl with ADD is basically a dreamer and very distracted.  One of her college entrance essays was on having ADD. She said it's not that a person doesn't pay attention, it's that they pay attention to EVERYTHING, and I think she was right.  She writes well, is a professional business writer now. Another college essay that I wish she hadn't deleted off the computer was on nanotechnology.

@ellerbracke The town we live in is supposed to have an excellent school system but as far as I'm concerned my kids both fell through the cracks. They should have been recognized for their abilities but my daughter was extremely shy so teachers overlooked her. She is great now but it really did change the course of her life. Unfortunately at that time, I was shy also, so did not advocate for them as well as I should have.

I used to be a very good speller but as I've aged I find I am not as good as I was. Like you, I know when something doesn't look right though.
JK