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

Learn Chinese Online with CLO - Go from absolute beginner to intermediate learner with our step by step, progressive audio lessons in Mandarin Chinese Read more.

ChineseLearnOnline.com

Glossika offers an audio method that consists of hundreds of bilingual sentences read by native speakers. They are selected to be natural-sounding and very common sentences and structured to build ... Read more.

glossika.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

If you're going to watch the world cup, do it in Chinese! Watching sports is an awesome way of learning a language, almost regardless of which level you're at. As a beginner, you can follow what's ... Read more.

hackingchinese.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

Description provided by OptiLingo (I have not yet tried this service myself): "OptiLingo is a hands-free language learning app that prioritizes learning Chinese through speaking rather than typi... Read more.

optilingo.com

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

A London-based school that takes their Mandarin courses to the next level - integrating technology (bespoke Phone Flashcards) and HSK test planning into their courses from Beginner, Intermediate to... Read more.

practicalmandarin.co.uk

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

Hanbridge Mandarin provides campus-based courses, online classes, and intensive cultural immersion programs. I don't know anyone who has attended any of their classes personally, but they cover the... Read more.

hanbridgemandarin.com