Jennifer's Teaching Toolbox: Various activities collected over her teaching career--feel free to use and adapt them as you wish!
Eidum's Teaching Toolbox
Dave's ESL cafe is a longstanding website with ESL-related teaching resources, including lesson plans for interactive teaching.
The BBC Learning English website is a resource focused on grammar, pronunciation, and vocabulary development. You can select lessons at the easy, medium, or hard levels.
The English Listening Lesson Library Online (ELLLO) is a resource focused on listening activities with English speakers with various of speaking speeds and dialects.