Estimation Jars

Example of an estimation jar table setup

Estimation Station

The Estimation Jar is always a huge hit at a Family Math Night event. Kids love to make predictions. And when there’s candy involved, it’s even more fun. Especially when the winner gets to take the jar home.

Watch the short video below for tips on setting up your Estimation Station.

Example of a K-2 and 3-5 estimation jar

K-2 and 3-5 Jars

I usually have two jars: one for K-2 and the other for 3-5 (or 3-6). The jars can be the same size or different sizes. If they are the same size then I put larger items, like Hershey’s kisses, in the K-2 jar.

It’s important to fill the jars with the same-sized items in order for students to make more accurate predictions.

Tip: Be sure to provide enough pencils as this is a very popular station.

Example of having a referent next to the estimation jar

Using a Referent

Sometimes making somewhat accurate predictions is hard. That’s when a referent - a little hint - can be handy. It’s a great way to develop number sense.

Cards for writing estimation jar estimates

“Thinking” Paper

Providing scratch paper is important for those students who need to jot down their thinking. Our Thinking Paper pdf works great!

Having a station facilitator manage the estimation table

Station Facilitators

I like to have at least one Facilitator managing the Estimation Table. They are there to make sure that each person enters only one prediction. If you decide to include the What Do You Notice? poster, then kids who share something they observe can enter a second prediction.

Tips for Setting Up Your Estimation Station

Estimation Slips

Choose one of the attractive estimation slips below to print out and use at your event.

Estimation jar sample slips

And the winner is...

It's hard to announce the winner at the event because it takes awhile to go through all the entries before everyone leaves. But you could give an end time to the entries (maybe 15 minutes before the end of the event) which would give the Facilitator time to count them. Otherwise, the winner is announced the following day. In the case of a tie, the two winners share the goods!