Wall Street Journal:

With school in full swing, many kids are shouldering hours of nightly homework. When students are stumped, they can turn to their (sometimes clueless) parents or head to a flurry of online homework help sites.
We looked around for sites appropriate for our sixth-grade tester. And we wanted help solving this geometry problem: what is a better buy? A square pizza measuring 8 inches by 8 inches that costs $10 or a round pizza with a 9-inch diameter that also costs $10?
Our first site was thebeehive.org. Created by the not-for-profit One Economy Corp. as a tool to help low-income families, the site offers easy access to information on a wide range of topics. By clicking on “school” on the home page (none of the other topics looked at all relevant), we got right to homework help. The section is divided into elementary-, middle- and high-school help.
Our answer was just a few clicks away. “Math” in the high-school section took us to Webmath.com, which offered a coherent explanation of how to do the problem along with a “circle calculator” on which to do the arithmetic. We went to “geometry problem solver,” then to “geometry-circles,” and there was the formula; we plugged in the information we had, the diameter, to get the answer: the square pizza is bigger.