Child's Play Math Video Tutorials: Unit 9 - Staircases
Unit 9 explains why staircases constructed with the rods are powerful math concepts.
Units 9 - 12 are available in a bundle from TES Resources.
Unit 9: Staircases; Unit 10: Mental Agility; Unit 11: Extended Staircases; Unit 12: Preparation for Multiplication.
https://www.tes.com/us/teacher-lesson...