The Algebra Tiles would be a nice tool to have students explore the distributive property. I like the way it is set up because it leads to students begin thinking about how things are factored, which can be hard for students to understand
Solve simple linear equations using a balance beam representation.
I like both of the balance scales. I really like how they have one that involves negatives while the other does not. Students have a hard time understanding how negative numbers fit into solving equations and I think this could help them. I might use this is the launch for a discussion amoung the students
Mr. Robb's Math is a YouTube channel containing 555 videos produced by high school mathematics teacher Bradley Robb. Mr. Robb's videos explain and demonstrate solving problems in Algebra I, Algebra II, and Calculus. Most of the videos are recorded while Mr. Robb is teaching. You can find the videos on the Mr. Robb's Math YouTube channel or visit Mr. Robb's website WowMath to find the videos organized in sequence with accompanying screenshots.