Base 10 Blocks with a number line and 10 by 10 grid
Base 10 Blocks (B10B) are helpful in modeling place value because a Ten rod is self-evidently equal to 10 Ones. This is an improvement over bundling straws, say, where you only know a bundle of 10 by counting them. A Ten rod, on the other hand, is another, greater unit of Ones.
There are two common ways of visually organizing counting past 10 with B10B: a number line and a grid. Both have advantages and limitations. I like number lines because they depict relative size, or magnitude, and this is what number sense is all about at this age. Grids, however, show number patterns horizontally, vertically, and diagonally very clearly.
Centimeter Number Lines
Number lines are a great way to build number sense and to model operations.
Centimeter rulers, centimeter number lines, and meter sticks can be paired with Base 10 Blocks and Cuisenaire Rods to model all kinds of math, including...