I Can Show Numbers In So Many Ways | Math Song for Kids | How to Represent Numbers | Jack Hartmann
First Grade Counting on Strategy Adding 1 Digit by a 2 Digit Number 1NBT4
6 . 132 ÷ 11
Double Digit Addition; adding numbers with 10's and 1's.AVI
Numbershark 5: Quick guide on getting started
Counting rods are small bars, typically 3–14 cm long, that were used by mathematicians for calculation in ancient East Asia. They are placed either horizontally or vertically to represent any integer or rational number.