Two-Color
Counters

Small disks with contrasting sides for sorting, counting, and representing two parts of a quantity.

Counting Number Sense Operations

What
they teach.

Simple materials.
Powerful mathematical ideas.

Counting

Move each counter once while pairing it with a spoken number.

Number composition

Use two colors to show different ways to split the same total.

Signed quantities

With an explicit convention, pair positive and negative counters to model zero.

How to use them.

Start with curiosity. Make room for discovery.

Build the total

Count out eight counters and keep that total on the table.

Show two parts

Turn some counters to the other color. Describe the red part and the yellow part.

Record a match

Write an addition equation for the arrangement, then turn one counter and record the new combination.

Try an activity

Find every split of eight

Arrange eight counters in a line. Begin with all one color, then flip one at a time. Record each pair of parts, including zero and eight. Explain how you know none are missing.

Give each color a clear meaning

For a first number-composition task, the colors simply show two groups. Six red and two yellow counters still make eight counters altogether. Keep the total fixed while exploring how many ways it can be split.

For signed-number work, establish a different convention: for example, red represents positive one and yellow negative one. One of each then represents a zero pair. Do not assume a learner will infer that rule from the colors or from an earlier addition activity.

A ten frame adds a useful structure to loose counters. Compare an unorganized collection of seven with seven arranged in a frame. Ask what the arrangement lets you see without recounting the whole set.

Choose your toolkit.

Find a format that fits your setting.

Check counter diameter, contrast, and quantity. Two-sided disks suit part-whole and integer tasks; two separate bags of colors are a different format.

Physical options link to Amazon. Illustrations show the material, not the exact product.