Sorting a Pile of Objects into Groups by One Attribute

You will meet this idea in ordinary days. Sorting is how laundry, tools, groceries, and mail all get handled. It comes before nearly every count. This is worth learning because sorting is the first step of collecting information about anything.

Watch for it today, and when you spot it, tell someone what you noticed and how you knew. Ask yourself where else the same idea might be hiding, then go and look.

Watch this carefully, friend. Sorting means putting things that are alike together. Take a pile of buttons and sort them by color: all the red in one group, all the blue in another. You could sort the same buttons by size or by how many holes they have.

Choose one attribute at a time, or your groups will get muddled. After sorting, count each group so you know what you have.

Watch out for sorting by two things at once. If you start sorting by color and then begin separating big red ones from small red ones, your groups become confusing. Finish one sort completely before starting another. If you get stuck, use your fingers or counters. Good mathematicians use tools.