This site by Jun Da contains a lot of very interesting resources for anyone who wants dig deeper into frequency lists. One set of data I haven't found anywhere else is a frequency list of syllables... Read more.

lingua.mtsu.edu

Mandarin Chinese With Fiona Tian is a free video resource for learning Mandarin Chinese in a fun, enjoyable way. Chinese doesn't have to be hard. Kick back, relax, and enjoy. Read more.

mandarinmadeez.com

Finally, Duolingo added a En->ZH course. As Duolingo is the most popular gamification learning app, the learning experience is relatively streamlined and tested. The monetarization aspect leads to ... Read more.

en.duolingo.com

This is the best overview of spaced repetition research I have seen online or offline. It's thorough, well-argued and probably covers more than you were looking for. It's not specifically about Chi... Read more.

gwern.net

A simple and easy to learn song to memorize China's major dynasties! Created for students of Chinese history at Harvard. Read more.

youtube.com

This is a course offered by Peking University and Coursera. It's free to use, but you need to register (you can preview it before you register, though). There are six units, each taking roughly one... Read more.

coursera.org

DigMandarin offer several interesting resources for free. The blog is a mix of directly useful resources, such as vocabulary for certain situations, and information/inspiration on learning Mandarin... Read more.

digmandarin.com

This site is a free resource for beginner learners of Mandarin who are looking to develop basic conversational ability for social, travel or work situations. It currently contains a small archive o... Read more.

mandarinhq.com

HiNative is a Q&A site where you can ask people all over the world about culture, language, anything. We support over 100 languages. Read more.

hinative.com

This is a story about looking Chinese but not knowing how to speak Chinese. It's an eye-opener for people who don't look Chinese and study Chinese, but it might also be painfully familiar for stude... Read more.

youtube.com

The Chinese Language Institute (CLI) offers free Mandarin learning resources in the form of articles on a variety of topics including Chinese characters, Chinese grammar and chengyu. They also offe... Read more.

studycli.org

This is a presentation by Thomas S. Mullaney about Chinese typewriters through history. In the digital age, typing in Chinese is easier than it has ever been, but how did the Chinese typewrite evol... Read more.

youtu.be

ChineseMe is the most integrated Mandarin course, designed for motivated learners who have decided to become fluent. It is an interactive textbook that adapts itself to your interests. The course i... Read more.

chinese-me.com

This is a research paper detailing a study of the mutual intelligibility of Chinese topolects. Dialects were sorted into groups and then it was experimentally tested how much of words and sentences... Read more.

openaccess.leidenuniv.nl

From their website (if you have personal experience of their courses, please leave a comment): New Concept Mandarin specializes in teaching Mandarin Chinese (Putonghua) as a second language. Act... Read more.

newconceptmandarin.com

This is a review of Perry Link's book about Chinese. This passage sums it up pretty well, and although I haven't read the book (yet), it's high on my list of books to get my hands on: "In writin... Read more.

lareviewofbooks.org