Discovery Education
Discovery Education: Web Math: Using a Number Line
This WebMath site provides an interactive number line "solver." Content includes helpful hint and a full explanation of the mathematical solution.
BBC
Bbc: Skillswilse: The Number Line
This Skillswise site focuses on number lines. Included is a video about how to use number lines, fact sheets and worksheets for instruction, and quizzes on the information presented. Be aware that this is from Great Britain, so any games...