I confess to a "doh!" moment when I read the week's assignment. Over the weekend a patron requested help with a high school research topic, and if I had consulted Britannica initially it probably would have helped me find useful resources for her a little more quickly.
My Britannica search on hydraulic fracturing turned up a good basic encyclopedia article, but I was especially interested in the "Expand Your Research" box that appeared on the right. The "Additional Readings" link had some very useful suggestions for books and documentaries. The listings under the "Journals and Magazines" link, however, seemed a bit out of date, with the latest article published in January 2011.
The Google translator could be useful for high school foreign language students or adults for whom English is a second language.
The World Atlas and World Data Analyst research tools would be a quick source for answering simple patron reference questions (What is the population of the United States? On what date did Maine become a state?).  The Video Collection could be useful for teachers and homeschooling parents. The links to current New York Times and BBC articles were unexpected; would patrons using Britannica be looking for today's news stories?