"Estimation Jar" is a popular math activity in Kindergarten!
To start, students are shown a jar filled with special items (sometimes candy!) that they will estimate the total amount of. After seeing a sample amount of the item, students write down their estimate of the total amount in the jar. When all the estimates are collected, Kindergarteners count the total number in the jar together. Finally, students determine whose estimate was closest, how close it was, and the reasons the estimates were close or not as close to the actual amount.
Estimation is an important skill we use daily in life and providing practice even to the youngest students allows them to develop this skill. As a higher-level cognitive skill, estimation helps students conceptualize and understand numbers as they develop their number sense.