Christopher Danielson recently released “A Better Shapes Book” for free on his blog. Before you read on, go take a look at it, download it, and enjoy!
Since some of my classes are studying geometry this trimester this was a fortuitous release. My students, who are in self-contained special ed classes, can identify benchmark shapes (squares, rectangles, triangles and circles), but we are currently investigating how squares and rectangles relate as quadrilaterals. This book was the best way for our students to explore shape properties without having to read, write and remember a lot of vocabulary. We were able to discuss what they saw and critique the arguments of classmates in a safe space, because all arguments were valid for one reason or another. The elimination of the potential to be flat out “wrong” created a safe space for my student population. As long as there was some semblance of justification, you were “right.” The students liked that!