I wonder how many kids will do their homework by hand if they find out that Wolfram Alpha can do most math homework for them.
For example, going to http://www.wolframalpha.com and type "solve x^2 + y^2 = 1 and x y = 1/2" will give you this page with graphs, symbolic and numerical solutions:
For some problems, Wolfram Alpha can provide step-by-step solution. For example, finding the derivative of 1/cos(x^2) gives the solution and related information. When we click on the "Show steps" link, we get to see this:
Integrals can be done easily. Typing "integrate 1/(1+ 2x + 5x^2)" and clicking "Show steps" gives you this:
Wolfram Alpha can provide step-by-step solutions for many of high school and college math problems I tried; standard math homework that asks the students to "show their work" would be easily done by Wolfram Alpha.