Swing Sets by David E. McAdams is a playful and powerful introduction to one of the most essential ideas in mathematics: the set.

Designed for children ages 8 to 12, this book taps into kids’ natural ability to sort, group, and classify objects—abilities they use every day—to gently lead them into the world of mathematical sets and set membership.

A set is simply a collection of objects where it is always clear whether a particular object belongs to the group or not. Sets lie at the foundation of all modern mathematics, from number theory and arithmetic to algebra, geometry, trigonometry, and even calculus. Learning the language, structure, and notation of sets early builds a deep and lasting readiness for advanced mathematical ideas.

In Swing Sets, readers begin with simple, concrete definitions:

"A swing set is a group of swings that hang from the same pole. A swing is something that swings back and forth that kids can ride on."

From this clear, child-friendly starting point, the book builds an understanding of what makes a set, how to define it precisely, and how to identify whether an object is a member of a set. Children learn how to form mathematical statements such as “f ∈ B” (read as “f is an element of B”), and how to translate such expressions into everyday language.

As you read Swing Sets with your child, you’ll be encouraged to explore together: Does an object in the book meet the definition of a swing or a swing set? Does an object outside the book belong in the set or not? These conversations deepen understanding and sharpen the child's reasoning.

Through definitions, examples, and gentle guidance, Swing Sets provides children with a joyful doorway into the logic and beauty of mathematics.