>>11635327Retard.
1st grade can easily get through the basics of arithmetic, i.e. adding, subtracting, multiplying, dividing.
2nd grade get onto more challenging arithmetic problems and a bit of (non-rigorous) geometry.
3rd grade would just be consolidating arithmetic and then starting with algebra, i.e. introducing variables etc.
4th grade you can start introducing set theory, and that opens up all sorts of avenues. Once you've defined relations and more importantly functions - especially polynomials, you can even now start with some basics of differential calculus, but can just go further with algebra, and introduce some more functions. Can also start axiomatic geometry.
5th and 6th grade: Basically doing stuff I listed in 4th, as well as introduce the unit circle and trig functions, hyperbolas, etc. Get into integral calculus, and probably can even introduce linear algebra and matrices.
You can probably fit some basic number theory and counting in there somewhere, but it really isn't necessary, since a lot of that comes with the territory.