Adults
ESL Lab - This site is good for listening practice.
English Page - English Page has activities to help you with both grammar and vocabulary.
A4 ESL - This site helps with everything! The podcasts are particularly good for listening practice.
ESL Video - more listening practice through video
Children
Bradley's English School - This site has interactive games to work on vocabulary, grammar and listening
PBS Kids - This site, for ages 6- 10, has video, music, games, and coloring pages!
PBS Kids Go! - This site is for older kids (10 - 13) where they can play games, solve puzzles and share their own stories.
ESL and Archie Comics - If your kids like comics, this podcast site could be really entertaining. For each comic there's a transcript, comprehension questions, and they can also see the comic in Spanish. But better if they don't!:)
ICDL -International Children's Digital Library - Fantastic resource! Loads of reading opportunities for your kids.