Week 48: Units

When is 100 + 100 NOT equal to 200?

I'm about to challenge everything you have ever thought about addition. After all, it's one of the absolutes in the world:

2 + 2 = 4
10 + 11 = 21
and...
100 + 100 = 50?

Every week, I would give my students a challenge on the side board; a brain teaser, a puzzle, or an interesting math problem. The ones that got the most traction were the number puzzles like the ones I'm sharing in this week's newsletter. The only hint I will give you is that this whole activity is a conversation starters for why the proper units matter. With that said, I'll open the challenge up to you:

• Choose at least one of the challenges.
• Solve the challenge with your child.
• Take a picture of their work.
• Include the picture in an email back to me.
• I'll pick at least one and send you a signed copy of Table Talk Math.

Here they are!!!

When does 100 + 100 = 50?
When does 100 + 100 = 3 1/3?
When does 100 + 100 = 60.96?
When does 100 + 100 = 1.5625?
​
As a bonus, come up with one of your own and send it my way to see if my boys and I can figure it out!
Thanks for joining the Table! If you have any questions, please feel free to contact me on Twitter (@TableTalkMath) or comment below. Be sure to have your friends sign up for the newsletter at tabletalkmath.com for weekly updates.

Thank you for taking the time to improve math fluency for children, one table talk conversation at a time.