# Tag Archives: Algebra

## “1+1=5”, by D. La Rochelle & B. Sexton. It is all about the units !

Last month, I attended a presentation about units (Cipparone & Bass, 2017). When C. Danielson (“Talking Math with Kids”) mentioned the book “1+1=5”, I quickly wrote the title on a Post’It, knowing that as soon as we were back home,  I would check it out.

I am so glad I did. Such a fun support to make children think about units.

Each page presents a drawing and an equation, such as a unicorn and a goat and “1+1 = 3?”. On the next page, the equation includes the units i.e. 1 unicorn + 1 goat = 3 horns. Indeed, 1 + 1 = 3 :-)

You may have read it in some of my previous posts, I always remind my daughter Rosie, 8, to provide the unit at the end of a word problem, and even invite her to write the units in her equations. This book was just perfect to reinforce my point, and led us to an instructive talk about the importance of the units.

Rosie LOVED that book, and could not stop talking about it for a week, finding new examples on her own. In fact, if you meet a little girl who claims, with a mischiveous grin, that “1+1 = 3”, enjoy: you may have just met Rosie :-)

Reference:

Peter Cipparone & Hyman Bass, 2017. Bringing Out the “Unit” Across Mathematical Domains. Cognitively Guided Instruction. 2017 National Conference, Seattle June 26-28.