Very nice graphics and that's some intense music for a game about growing seeds.  It made me concentrate more on my order of operations than I've needed to in a long time.

The game didn't fit on my screen and resizing my browser didn't work because the on screen numpad didn't scale the same as the rest of the game, so I was forced to keep scrolling up and down to see the problems and type the answers.  Also, my numpad also didn't work.  My number keys on the top of the keyboard worked fine though.