First up, try "Salsa" for the kids! This a television series with numerous episodes available online. Every episode is a mix of puppets (think Sesame Street style) and humans. The entire episode is in Spanish, but is presented in such a way that it is easy to understand. Each episode also focuses on specific vocabulary or ideas. http://www.gpb.org/salsa
Have you ever considered watching Cartoon Network in a foreign language? Try Cartoon Network's Mexico version! http://www.cartoonnetwork.com.mx/#/home
For fun Spanish games, check out Online Free Spanish.com There are a variety of games with a variety of skill levels for each. http://onlinefreespanish.com/
To learn basic phrases and vocabulary, consider downloading Byki. There are two versions - the free one, and a premium (pay for it) version. The free version has enough phrases and vocabulary to at least get you started. It is set up flashcard style, and most of the flashcards have a picture to go with the words making it easier for those of us that are quite visual. Byki is probably better for older kids and adults as it isn't fun and flashy like the above two resources. http://www.byki.com/
Study Spanish Free is heavily focused on grammar with several online lessons and exercises. It allows you to create an account so that you may track your progress. Lots of free content, but also some "premium" content. Definitely for older students and adults... http://studyspanish.com/freesite.htm
Web Spanish Lounge is a mix of videos, audio, news stories and articles, and actual lessons. It is set up a bit like a blog. http://studyspanish.com/freesite.htm
Updated to add Duolingo! I just found Duolingo, and have played around with it a bit. Duolingo is interactive, with immediate feedback. It uses pictures, highlighted text, audio, and more to help you learn.
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