Focus on Math

Helping children become mathematicians!

Building Numbers: A Kindergarten or Primary Activity January 23, 2014

building numbers chips 2

I visited Mrs. Merrill’s kindergarten class today. The focus of the math lesson was on building numbers to 10, we did this with a large organizing sheet (11” x 17”), some small dot cards (each student had a set of cards 1 to 10 — download below), and small bingo chips. Students were asked to place a dot card over each square on the paper, and then use the bingo chips to make another set the same size in each box.

Some students chose to lay their cards out in rank order, while others were happy to just lay the cards in any order they pulled the card out the small bag. We also noticed some students organizing and building left to right in the boxes, while others built randomly on the page.

building numbers chips 1

The organizing sheet is very “generic” on purpose allowing it to be used in a variety of ways. The number for building can be generated by a dot card, by rolling a die (or dice), by placing a number word card (e.g., “two”) over the square, by dropping a bean onto a 100 chart, etc. Students can build the number with counters, with little ten frames (I find children love to work with tiny things!), with base-10 blocks, etc.

building numbers 10 frames

I have not figured out how to put a large 11 x 17 paper into Dropbox, but if you will print out the template you want onto legal-sized paper, you can then enlarge at a copier 121% and it will fit the 11 x 17 page rather nicely.

I have created templates for building 8 different numbers as  well as for building 10 different numbers. The latter could be used for 100 Day activities by building 10 in each space for a total of 100.

Dot cards can be downloaded here as well.

I hope you are able to use the activity in one of its “versions” in your classroom!

Mathematically yours,



100 Day! February 16, 2012

It is that time of year again when primary classes are celebrating the 100th day of the school year. Many primary teachers count the days of school each day in their “calendar” time with children, creating groups of tens with straws, Popsicle sticks, 10 frames or such. So it is a “bid deal” when there are finally 10 groups of 10 to make 100.

I have been part of a math collaboration group with teachers at Alwin Holland Elementary School here in Fort St John, and today they were celebrating 100 day. I joined in one of the activities that students rotated through in groups. Mrs. Hollman and I had arranged for students to make “Fruit Loop necklaces” by stringing the cereal “o’s”. In order for the students to keep track of how many they had put on their strings, we had them string 10 of a single colour, then switch to a different colour for the next 10. The floor was crunchy with crushed cereal by the time all four groups had cycled through, but it was a delightful afternoon! I am sure all of the other stations were equally successful.

And remember, if you have missed counting school days, you can still catch up by counting days in the calendar year. The 100th day this year will be April 9th since it is a leap year! For older students it would be a great day to focus on hundredths and percents.

For more ideas about what kinds of things to do for 100 day, check my blog from last April 5 and 7.

Mathematically yours,


More on 100 Day! April 5, 2011

With the 100th day of the calendar year coming up soon, I thought I would post a few more ideas for activities involving 100. Hopefully some of them will be useful to you with your students. So in no particular order…

  • Read 100 Hungry Ants to your kids and have them divide 100 by other numbers. Ask how many groups? How many in each group? How many left over? (A 100 dot array is a useful tool here — kids can circle groups they are making right on a small 100 dot array and to figure out the answer for each group size.)
  • Give young students (grade 1 or 2) a 100 chart (either 0 to 99 or 1 to 100) and say random numbers for them to find and cover with a bingo chip.
  • Have students figure out how far to 100 (or to 100%). Again, a 100 dot array is a useful tool. Given a certain number or percentage, e.g., 23 or 23%, have students figure out how much is needed to get to 100 or 100%.
  • Pour out 100 candies such as jelly beans, Skittles, or Smarties and graph them by colours.
  • Have students close their eyes and stand when they think 100 seconds have passed.
  • Cut pieces of string, estimating 100 cm. See who can come closest to the actual amount (graph the estimated lengths).
  • Have students bring in 100 of the same item from home (e.g., pieces of macaroni, Lego blocks, pieces of gum, mini marshmallows, bobby pins, etc) and weigh the different amounts.
  • Have students jump rope 100 times and then take their pulses. Graph and compare.
  • Hold a 100 second race.
  • Create pictures using only 100 cm of yarn or string.
  • Use large 10 x 10 grids and have students colour them in two colours to make a pattern or picture.

There are lots of things that can be done to celebrate the day. I am doing several of these activities with my eight classes of students at Charlie Lake School this week. No matter your grade, it is always great to put some fun in math!

Mathematically yours,