For 3 years in a row I had the highest student scores in the district. I do sometimes switch your and you're, and occasionally their and they're. I think I hate the apostrophes.
I am a child of spellchecker. But, trust me, I know the difference, and I know when they are right and wrong, and when it matters (not here) I take better care.
Shall we deal with a real issue? Like the fact that you seemed to notice "seryous" (an obvious one) but you missed "your?"