Create your own centimeter ruler. Then, estimate and measure with lengths with it. Warm up with a Mystery Math Mistake as you add two 2-digit numbers using a decomposition strategy. Think through ...

It’s the attention to detail that often differentiates a good product from a great product, but designer Norihiko Terayama goes above and beyond the call of duty with his f,l,o,w,e,r,s ruler, which ...