One of the problems with PS - they want to treat everyone the "same" and they're all so very different.
My oldest was obsessed with China for a long time. He did learn Chinese. But I built entire lesson plans around China. History, Math (converting Chinese li in to miles. Figuring out how much it cost to build the Great Wall then versus how much to build now (or back in the 90s anyway).
He watched an entire College level lecture series (The Teaching Company) on Early Egypt. Took notes (to practice his handwriting, listening skills, and note-taking technique). I think it was 9 hours - or maybe 18. He was about 9 or 10. Took a few weeks - or maybe months.
Took an online Chemistry course designed for kids. Started an Algebra textbook at 9. (Frankly I held him back because it wasn't a teachers edition and I had to relearn Algebra to work the problems to see if he got them right! 
) If we couldn't, one on the mom's in our group had her Master's in Math.
His handwriting still looks like a primary schooler. He has dysgraphia - for all the reasons, not just one of them - so damn near impossible to correct completely, though he has compensated fairly well over the years. He can spell anything outloud, but used to misspell his own name when writing. (Mom, my hand can't keep up with my brain!!)
I pulled him from PS when he was in 2nd / 3rd grade (split classes - though he was also taking the AG 5th grade supplemental classes, too) when they wanted to move him from the AG (Academically Gifted) program to the LD (at that time Learning Disabled program). What? He suddenly stopped being SMART?? I presented REAMS of evidence that you play to the strength and accommodate the weakness. Long ugly political story. HS was supposed to temporary (for half the year), but he LOVED it so much and advanced to fast, we hadn't the heart to make him go back.
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