Elementary school is for children who are four to eleven years of age. Basic elementary school maths is the start of that age range, so counting with your fingers, the idea of base-10, and adding two small numbers with perhaps one carry. Late elementary school (for me "middle school", but the UK reforms education too much and too often to keep track) was still only basic arithmetic, fundamental "roll 2 d6" probability, nets of the most basic polyhedra.

Algebra and trig wasn't until secondary school for me ("year 7" we called it, school year beginning age 11), though I personally had a head start from having learned to read with the Commodore 64 user manual.

Well, if you're not willing (or well calibrated enough), I should get some old exam papers, see how well it grades against students. I wonder if there even are any downloadable pre-GCSE exams…