In this Mystery, students use estimation and graphing to discover the surprising difference in the amounts of fresh and salt water on Earth.

The Physical Activity Guidelines for Americans recommends that youth (ages 6-17) engage in at least one hour of physical activity daily.

In this task, a group of children sit around a table. Without peeking, they figure out how many feet are under the table.

This activity is a valuable opportunity for students to think about estimation and making visual justifications related to the approximate number system.

This activity is a valuable opportunity for students to count, visualize number quantity, think about estimation, and to make visual justifications related to the approximate number system.

How many times have you come across a tree and thought that tree is humongous?

Estimating might sound like an activity from young children, and although it is fantastic for them to estimate how many pieces of candy are in a jar or how many crackers come in a box, older students can also benefit from these and take them to the next level.

While sitting around the table, ask your student to figure out how many feet are under the table without looking.

Unfortunately, real world math lessons are sometimes learned from tragedy. 

Two sample problems are included that demonstrate how Google Earth can present estimation problems involving area. 

Children extend their investigation of the previous day to include nickels.

In this lesson, children listen to a poem about money, and then examine a quarter.