PBS
Pbs: Balancing Scales to Solve Equations
Predict the number of blocks you need to equal the weight of one bag and then test your theory. This interactive exercise focuses on using critical thinking skills to add and subtract items on the scales to achieve balance and visual...
National Council of Teachers of Mathematics
Nctm: Illuminations: Pan Balance Numbers
Use this tool to strengthen understanding and computation of numerical expressions and equality using a balance scale.