Hang on. All we know is that the father is more intelligent than OP. And that he can’t understand the maths his farther teachers.
Perhaps OP is just real dumb and his farther is a high school teacher.
Could be but I promise you, smart people can 100% be stupid too: Everyone does dumb shit sometimes.
smart people can 100% be stupid too
To expand on that, people can be smart in one aspect and really fucking dumb in others. Intelligence is a spectrum, it’s not binary like you’re either smart or dumb. Plenty of people who understand quantum level physics etc. who are socially and emotionally at the level of children and vice versa and so on.