Since the red and green number cubes are opposite of each other, when they are together on the same side of the balance, their value is zero and may therefore be removed without affecting the balance. A video introduction is provided for each lesson. (See the sample YouTube video at http://youtu.be/VFYQ47EAqZw.) Each video introduction is followed by two examples and ten exercises. It is essential for the student to view the lesson video prior to attempting the examples and exercises for that lesson. Hands-On Equations is the ideal introduction to algebra for elementary and middle school students. Not only will students have fun and be fascinated with the program, their sense of self-esteem will be dramatically enhanced as they experience success with sophisticated algebraic equations. High school students struggling with algebra will likely experience success and understanding for the first time as they work with this app. More information on Hands-On Equations can be found at www.borenson.com and on YouTube.