Spring brush up of Japanese language skills

I came to Japan a long time ago, and before I arrived, a year of Japanese language education was all I had. That brief instruction provided me a foundation in grammar, a few hundred kanji, and a smattering of expressions. It's been a long road to communicative use of Japanese. I get along adequately in face-to-face communication at work and in my social life. But I still have a way to go with reading, writing, and idiomatic usage.

Samoona's recent blog post about her Japanese language learning journey gets me thinking about free resources I keep returning to.

Tsunahiro

Tsunahiro is a program of the Japanese Ministry of Education. Videos of authentic interactions, transcripts, and vocabulary banks introduce practical Japanese. It provides a level check, too. The resource tops out at the equivalent of CEFR B2. Even though I passed the Japanese Language Proficiency Test (JLPT) at N2, I still have some ticks, and Tsunahiro's resources humble me! I have listened and read the transcripts to polish my expression now and again.

Tae Kim's Guide

Tae Kim's Guide to Learning Japanese, published on Kindle and in paperback, is available for free on the website. The guide provides a wide range of grammar, expressions, and vocabulary with easy-to-understand explanations. Unlike most Japanese textbooks, which focus on formal Japanese, the guide provides examples of casual usage. It's great for getting along at work and at play.

NHK Learn Japanese

For an easy entry to learning Japanese, suitable for newcomers and visitors, I recommend NHK's Learn Japanese. Click on the level chart to see which programs meet your needs, from essential to "magical"!

Exposure to Interaction

Samoona mentions community language lessons. These are provided by 国際交流協会,

kokusai koryu kyokai, international centers. They provide Japanese (and sometimes other languages) lessons for free or at a low cost.  While the majority of the volunteers who "teach" the lessons are not professionals, interaction with them provides insight into the usage and meaning of the grammar and expressions that you're working so hard to acquire.

How did you learn Japanese? What resources do you recommend for a beginner, intermediate, or advanced level learner?