Marcey,
You may want to ask Haydn what
she wants in terms of math. She truly is old enough to express her desires, just like she does with all her other subjects.
We tried "unschooling" math with miquon stuff, tangrams, pattern blocks, geo boards, etc. At exactly 2 my oldest dd (profoundly gifted) said, "Mom, why don't you just get me a book that has math in it and teach me math? Wouldn't that be easier?" We got a couple different curricula, and she really liked (and still likes) Saxon, despite all the evil things people say about it, especially for gifted kids. She's ten lessons from finishing grade 3 right now.
I think unschooling is fine for kids who aren't mathematically gifted, but to truly delve into deeper math thinking, a curricula is almost required. There aren't a whole lot of handy calculus examples in daily living.
Oh, if you truly think Haydn is gifted in math, you may want to look into the EPGY program at Stanford. It's a distance-learning math course for gifted kids, and the examples look pretty fun. We considered enrolling Dagny, but we're doing fine with the program we have-- so if it isn't broke, we aren't fixing it! But we probably will use this program when she gets into higher level math, mainly because she can earn college credit that way.