Former math & science teacher makes story tutorials and fun games to teach the hard concepts. Can you pick the right (x,y) coordinate for Whack-A-Mole? Fly a dragon to get gems with y=mx+b? Or balance chemical equations? Used by teachers since 1995, 60 million pageviews. Free Services Offered: Algebra coordinate plane graphing (x,y) y=mx+b, balancing chemical equations, chemical elements and symbols. Math, science, chemistry.