Sunday, February 1, 2015

Building Number Sense on a 100 Chart

Yes, yes, yes, it has been a while since my last blog post. I'd like to not have so much time in between them but life kind of gets in the way of that!! :)

I am here today to bring you a number sense game that I use as a daily warm-up, but can also be used as a whole group, small group or math center/station activity.

Building number sense is something that all grade levels should must have to, have to can do. ;) It is especially important for K-2 to build number sense in order to lay the foundation for higher level math. (Not to mention that number sense is needed to do everyday activities such as cooking, games and playing sports!)

One tool you can use to help build number sense is the 100 chart:

The activity I want to share is called "Arrow Arithmetic" in It Makes Sense! Using the Hundreds Chart to Build Number Sense (click below to view the book).

In this activity, students will receive a clue such as:
and will use the 100 chart to figure out the answer. So how do they figure out the missing number??? They have to use the arrows and some number sense! 
Each arrow represents a direction you can go on the 100 chart: left (-1), right (+1), down (+10) and up (-10). Students can use a 100 chart to determine that the missing number is 45. Eventually, students will be able to determine the answer using mental math and even be able to solve problems that include diagonal arrows. And what does that eventually lead to?? Being able to add and subtract two-digit numbers using mental math!

Pretty cool, huh?!

I urge you to give this activity a try. My students LOVE it and beg to play it every day (which lately, we have been doing)! And they are REALLY good at it. :)

I made a little activity pack to go with the Arrow Game activity from the book:

The pack includes two sets of arrow cards, 1 easy and 1 challenging. Also, allow students to self-check with QR codes:

I have also included a few practice pages:

It's even on sale for SuperBowl Sunday!

Check out the activity here:

P.S. Need some 100 charts for your class? I've got a set for your FOR FREE! Click below!


  1. Love this activity - we have done 1 more, 1 less, 10 more, 10 less, but this is a great extension. Thanks for sharing this idea. I will need to check out your product too!

  2. Janaye- I just bought this book on Amazon and love all the ideas. I am working on a table top 100 chart for my small group area to do these activities in math rotation. I instantly went to your shop and bought the unit. This will be great because I am amazed at how many kids still struggle with this concept. I ended up purchasing the Number Sense book, and the Tens Frame book as well! I love your blog! Thanks for always sharing such great ideas!!