Here is a great little resource for students. After clicking through it, it's probably appropriate for 4th grade and up. The site is well organized, and while its presentation is relatively free of political or sticky historical issues, it is a great resource for general interests. They have links to historical information as well as current pop culture trends. While it is a very brightly colored and simple to navigate, the information serves as a nice introduction and would be a good starting point for any kind of research assignment. It's a pretty well-curated, and definitely a better resource than a google search or wikipedia.
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