You can search Google and Wolfram Alpha at the same time. This is a handy tool for educators and students alike. Wow. (I wonder how long Google and Wolfram will let it stay - awesome while it lasts, though.)
Here's the page where you register your school for Bing for Schools - you'll need to enter all outbound IP addresses so ask your IT department to do it.
This is a very comprehensive list. One area where Wikipedia excels (if academics will continue to contribute) is in comprehensive lists of open education resources. This list includes whether it is subscription or free and what type of database it is.
A method for facilitating student search using the i-search method. There are 4 phases of using this method and the website says that it is an excellent method for "alternative assessment, inclusion of students with diverse learning abilities, and technology integration." I found the method via a New York Times article on teaching students how to search.
New Search Engine from ex google engineers plans to compete with Google - Called "Cuil" - this article outlines the story.
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