ALA Booklist (Sat Oct 01 00:00:00 CDT 2016)

While most children's books on circles simply identify the shape and give examples of it, Adler and Miller take things a step further by challenging elementary-school students to grapple with some basic geometric concepts. The book relies on readily available supplies (paper, a pencil, a ruler, scissors, a round dish, a can) for a series of activities designed to build a child's understanding gradually, one step at a time. The concise, methodical text explains simple, hands-on ways to determine a circle's diameter, radius, and circumference. Readers will pick up vocabulary such as arc, chord, sector, segment, and tangent along the way. Next, they'll find out how to determine the value of pi and how to use it in finding the circumference and area of a circle. The clarity of the illustrations is achieved partly by leaving out extraneous details, but Miller's brightly colorful digital pictures always project a sense of fun. A companion volume to the writer and illustrator's Triangles (2014), this well-designed book offers an unusually clear introduction to the basic geometry of circles.

Publishers Weekly (Fri Oct 06 00:00:00 CDT 2023)

Frequent collaborators Adler and Miller follow their books on fractions, time zones, triangles, and other topics with a thorough look at all things circular. After a brief run-down of two- and three-dimensional shapes with round aspects (cylinders, cones, spirals, etc.), Adler dives into what makes a circle a circle, unloading a significant amount of vocabulary along the way, including words like symmetrical, diameter, sector, and chord, all clearly explained in direct writing, assisted by hands-on project ideas and Miller-s playful circle-based animal portraits. By the time children get to the closing line--We live in a world of circles--they-ll be convinced. Ages 6-10. (Aug.)

School Library Journal (Mon Aug 01 00:00:00 CDT 2016)

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 spacescomplete 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. VERDICT Extremely useful for the classroom at home or in school, and very approachable in its colorful minimalism. Patricia Manning, formerly at Eastchester Public Library, NY