Lesson 4

Which Picks Up More?

Est. Class Sessions: 4–5

Before the Lesson

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Absorbency can be a difficult concept for third-grade students to grasp. This lab challenges students to determine which paper towel is the most absorbent, but we ask, “Which towel picks up the most water?” and “Which towel is the better 'picker upper'?” Students are not expected to fully understand the complexities of absorbency in order to complete the lab.

In this lab, a common misconception that students have is that the towel that looks the wettest is the towel with the most absorbency. After dropping water onto towels, students may believe that the towel with the spot that has spread to cover the most area is the most absorbent. In fact, just the opposite is true. The towel with the spot of water that stays concentrated in the smallest area is the most absorbent.

Prepare Students to Make a Bar Graph. Use DPP items F and I to prepare students to make a scaled bar graph in this lab. Previously students made scaled bar graphs with specialized graph paper with guidelines. In DPP item F, students are asked to use a grid without guidelines. In DPP item I, students are asked to scale the vertical axis by fives and graph a set of data. In the lab, students will be asked to choose an appropriate scale for each set of data and make a graph on Centimeter Graph Paper.

Organize Student Groups. The Better “Picker Upper” Lab works well with cooperative groups of two to four members. Arrange student groups prior to the lesson. The lab takes approximately four to five class sessions.

Student Guide:
Student Activity Book:
Master: