One of the new resources I have been exploring over the past few weeks as the result of my involvement in Math Rocks, a community of teachers in my school district working together to build relationships and spread the love of math, is Estimation 180. This website includes a plethora of images from the real world where students have to estimate some figure in regards to what is represented in the picture. For an example, see the picture below.
The website is organized by days. As of today, the site is up to 220 days; therefore you could use this website everyday for 220 days and get a different picture each day. Wow!
Here’s how it works:
1. Choose an image.
2. For each image, have students answer the following questions:
- What estimate is too low?
- What estimate is too high?
- What is your estimate?
- What is your reasoning? Begin with, “I noticed . . .”
One of the other teachers in the Math Rocks community used the phrase “Mathematize Your World” to describe what is happening in these images. I love this phrase because that’s exactly what students are expected to do. They are looking at ways that we use math in our everyday lives. How many times, looking at Image B, have we looked at a large container of something and needed to estimate how many smaller containers could share the contents of the large container? First day of school snacks, i.e. Goldfish? Estimation is part of what we do everyday.
This activity is an excellent opportunity to encourage students to communicate their thinking to others in pairs or small groups. After allowing students some think time to answer the questions above, allow students to share their reasoning with others and then do a class share-out. I’m not sure about you, but I just thought of a new starter— Mathematize Your World Monday with Estimation 180.
Not only does the website provide rich opportunities for students to use their estimation skills and discuss the reasoning they used to arrive at their estimation, but the website uses a Google form so that students can share their estimations with the world. Estimations could be submitted as a class, after agreeing on the estimation to submit, or individual students can submit their own estimations. After submission, students can access the contributions of others via the form results sheet. And yes, the correct answer is revealed during this process.
