MS Math Add-In for Word 2007

I mention this because this is just the thing I've wanted to be able to check my kid's math homework: the Microsoft Math Add-In for Word 2007.

For example, after installing it, I can open Word, press Alt+= to get myself a new equation and then enter:

x^2 +2x + 2 + 3x - 4x^2

it translates into:

If I right-click and choose Simplify, I get the following:

If I right-click again and choose Plot in 2D, I get:

If I've got an equation that I want to solve, I can enter it:

and then right-click and choose Solve for x and get all the possible solutions:

This even works if you have multiple equations with multiple unknowns, which means this is good through at least 8th grade Algebra. Wahoo!