Give homework where the most interesting part is not something that Wolfram Alpha can solve.

I remember university teacher of mine had a collection of a few problems which if you typed it into Mathematica would give an answer on a very different form than what you would be likely to get if you solved by hand the 'normal' way. Handy for giving you a heads up on who might be 'cheating'.

Same is true here. Look at the solution to the quadratic in the beginning. I suspect most students would use the quadratic formula and not complete the square by hand.

Assume learning by doing, and Alpha's ability to solve any introductory problem, and you are screwed.

There have always been ways to cheat at basic school work, if nothing else by grabbing someone who did know how to do it and copying theirs. This does add one more way, but it can also be constructive if struggling to learn something.

You'll be able to tell who those kids are because they'll die on the exam.

I've been offering these kind of calculators for a while to students... but the department doesn't require a grad their homework. Is this college? What college department requires that sort of thing?

It is a college:

http://www.math.nyu.edu/courses/Calculus/2009/Fall/122/hw.ht...