Today I assembled our One Fish Two Fish Estimation Center. You can click on that link and get the free download from my Teachers Pay Teachers store.
Here’s how I put this estimation center together. I started with a goldfish bowl from Walmart.
I lined the glass bowl with a plastic bag before I put the colorful goldfish in because I don’t want my students to breathe all over the helpless little crackers.
I tied the bag with a red ribbon.
I printed the instruction sign and entry forms and set them out at the center with pencils. It looked like this.
When students came to the library, the estimation center looked like this.
They were excited at the possibility of winning all the goldfish! But I felt like the center was more of a guessing game than a math center. I wanted to connect this library center to their classroom learning.
I asked a second grade teacher how she taught estimation, and then I made some upgrades to the center.
I added hundred charts all around the edge of the table. I found a free printable hundred chart online here and I made copies. This second grade teacher told me that in class, they think about putting one object on each square of the hundred chart. Will they fill the whole hundred chart? Will they fill more than one hundred chart? How many?
I also added this to the center.
I had an empty Petri dish, and I put 10 goldfish in there. Now the students can use this visual image to estimate how many groups of 10 might be in the bowl. (I didn’t want to put the 10 goldfish in a baggie because I thought they might get smushed into crumbs.)
Now there are a couple of different mathematical ways to try to make an estimate, by tens or by hundreds. As for the correct total, I have to say that I did NOT actually count every single little goldfish. There are over 1000 in there! I used the serving size and amount on the nutrition label, and I multiplied those. So far, no one is even close. They are all estimating way too low.
I like the opportunity to bring math into the library, and the goldfish are a colorful addition to our decorations. If you’d like to try this in your library, you can download the printables for free!