Whatever language you teach or are trying to learn, this should help you a great deal…
The Center for Open Education Resources and Language Learning (COERLL) is one of fifteen Foreign Language Resource Centers in the United States (http://www.nflrc.org), more precisely, in Austin, Texas. It is mainly funded by the US Department of Education as well as private donations. Its general mission is to « improve the teaching and learning of foreign languages by producing resources (materials and best practices) that can be profitably employed in a variety of settings ». What does that mean? Well, they create or round-up content for teaching a total of 18 languages including American Sign Language, Arabic, Chinese, Grench and Spanish. This educational material is offered freely online for anyone to use as they please.
But what can you find on their website – http://www.coerll.utexas.edu/coerll/ ?
First, in the Projects tab, you will come upon various teaching materials on less commonly taught languages, tools (such as helpful apps), instuments to assess bilingualism and professionnal development instruments for language teachers. Also, in the Materials tab, you will find language classes/activities/documentation for free on a total of 18 languages. For example, you can find exercices to practice your Chinese, or videos to practice your Amercian Sign Language.
I invite you to give it a look and browse through the different tabs. Its the best way to really experience it.