Estimation Station

There are so many great preschool blogs and resources available to help me out when I am stuck for an idea or just need a lesson to inspire my plan book.  My go-to blog is PreKinders by Karen Cox.  Frankly, I think she is a genius.

Last year, I was looking to ramp up my math centers a bit and I came across Karen's brilliant idea for teaching kids to estimate.  When I think of estimating, the image of a giant jar of candy corn or gumballs at a fair comes to mind.  Most of us probably don't guess the correct answer within a hundred!  My preschoolers are still working on number concepts to 10 and 20, so I had completely written off the estimation jar because of its impracticality.  Lo and behold, here is a developmentally appropriate, kid-friendly estimation station.

We switch out the objects each week, and the students love to come in and see what we have put in there.  This week it will be wooden beads.

In September, we began with a simple apple estimation.

The key to teaching preschoolers to estimate is to give them a point of reference.  In the apple example above, the first box that contains 1 apple is labeled with a "1", the 2nd with a "2" and the 3rd with a "3".  The fourth box is labeled with a question mark (or a "Mystery Mouseketool" as some students call it!).  I always talk with the students about the mystery box.  Does it look like it has more than the other boxes, or less?  Can you think of a number that is more?  That would be a good guess.

Last week for Halloween, we estimated zombie eyes made out of ping pong balls!

The first box had 4, the next had 6, and the third had 8.  The mystery box clearly had more.  Many students still guessed 3, 6, 7, so it's obviously a work in progress.

It helps to utilize a big number line.  We set the boxes on their corresponding number, and then the students have to work to place the mystery box in the right place.  

To make the guesses, sometimes I have the students record them on a little slip of paper.  (Prekinders has a recording sheet here, and I made this generic one that we can use each week.)  

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Background image is from www.mycutegraphics.com

Other times, I will set out big numbers and have the students stand next to their guess or we will just discuss it and record their guesses orally.  There are lots of options to keep it interesting!

I'd love to hear other ideas about how to incorporate estimation in a developmentally appropriate preschool classroom setting.  Have fun playing and learning with your children today.