Which One Doesn’t Belong? Wins Mathical Award

Which One Doesn't Belong w awardChristopher Danielson, a mathematics author, teacher, and curriculum developer from Minnesota, has won the Mathical Prize for his book, Which One Doesn’t Belong? A Shapes Book.

The award will be presented to Danielson on April 22 by the Mathematical Sciences Research Institute (MSRI) at the National Math Festival in Washington, DC. Danielson won the award in the Grades 3-5 category.

“For a number of years I have longed for a better shapes book,” said Danielson. “I wanted a shapes book that gives space for noticing relationships, asking questions, and thinking together,” said Danielson. “I designed Which One Doesn’t Belong? to be an invitation to a mathematical conversation.”

The book–which is intended to be used by children, parents, and teachers–features sets of four shapes with the recurring question, “which one doesn’t belong?’ Any of the shapes can be the right answer; the key is getting kids to justify their answer in their own language. The school version comes with an extensive teacher’s guide, including an “answers key” that describes one possible argument that can be made for each shape in the book. Which One Doesn’t Belong? and the teacher’s guide can both be ordered from Stenhouse.

Which One Doesn’t Belong? encourages children to use mathematical thinking to explore new concepts,” wrote the committee who awarded the prize. “The layout is brilliant and in classroom testing, children were active readers, enthusiastic to share their insights and justifications in the discussion. Perhaps the best feature is that questions have no single, simple answer!”

Danielson has worked with math learners of all ages—12 year-olds in his former middle school classroom, Calculus students at Normandale Community College, teachers in professional development, and young children and their families at Math On-A-Stick at the Minnesota State Fair. He designs curriculum at Desmos. He is the author of Common Core Math For Parents For Dummies, the shapes book Which One Doesn’t Belong?, and the forthcoming counting book How Many? He blogs about teaching on Overthinking My Teaching, and for parents at Talking Math with Your Kids. He earned his B.A. in mathematics from Boston University, his M.A. in Education from the University of Michigan, and his Ph.D. in Mathematics Education from Michigan State University.

The Mathical Book Prize is organized by MSRI in partnership with the National Council for Teachers of English (NCTE) and the National Council for Teachers of Mathematics (NCTM).

Add comment April 21st, 2017

Now Online: Which One Doesn’t Belong?

Danielson’s book reveals the wonder and freedom of expression that many children don’t often experience in mathematics. A single, simple question puts children in a position to speak mathematically even at early ages. Ask students of all ages “Which one doesn’t belong?” and revel in the reasoning and conversation that results.
—Dan Meyer

How can I recommend this highly enough? Christopher Danielson emphasizes the stimulation of curiosity and that math is about making precise things that we—and children—can informally observe, without having to learn any mathematical language first. Which One Doesn’t Belong? is a glorious book for adults and children to explore together, and the Teacher’s Guide makes it into a profound mathematical resource.
—Eugenia Cheng, pure mathematician, University of Sheffield and School of the Art Institute of Chicago, and author of How to Bake Pi

Which One Doesn't Belong student bookWhich One Doesn’t Belong? is a children’s book about shapes. More generally, it’s a book about mathematics. When children look for sameness and difference; when they work hard to put their ideas into words; when they evaluate whether somebody’s else’s justification makes sense—in all of these cases, children engage in real mathematical thinking. They build mathematical knowledge they can be proud of. They develop new questions. They argue. They wonder.

In the accompanying teacher’s guide, author Christopher Danielson equips teachers to get maximum benefit from Which One Doesn’t Belong? Through classroom stories, he models listening to and finding delight in students’ thinking about shapes. In clear, approachable language, Danielson explores the mathematical concepts likely to emerge and helps teachers facilitate meaningful discussions about them.

You can preview portions of the teacher’s guide online now!

2 comments August 4th, 2016

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