Circles

Gr 2–4—In this companion volume to his equally attractive and useful Triangles, Adler addresses the geometric world of circles. Starting with an introduction to the realm of noncircles (spheres, cylinders, cones, etc.), he then launches into circular spaces—complete with centers, points, diameters, radii, chords, and other potentially unfamiliar terminologies. Simple, logical activities are presented to drive concepts home, including popping into the world of pi and challenging young geometers to find the areas of a gaggle of bright circles. Miller's bright illustrations provide an excellent guide for the experimental activities. A glossary is appended, as are solutions to the challenges in the text. Math teachers and homeschooling parents will be delighted with this clear, concise overview of a familiar shape with unexpected details.