Paper Towel Testing GEMS Project

5.1A: demonstrate safe practices during field and laboratory investigations
5.1B make wise choices
5.2A plan and implement descriptive and simple experimental investigations including asking well-defined questions, formulating testable hypotheses, and selecting and using equipment
5.2B collect information by observing and measuring
5.2D communicate valid conclusions
5.3B draw inferences based on information related to promotional materials for products and services

CONCEPT STATEMENT: The Texas Essential Knowledge Skills are explicit when they state that students will “conduct field and laboratory investigations following home and school safety procedures and environmentally appropriate and ethical practices,” and “the student uses scientific methods during field and laboratory investigations.” The Benchmarks for Science Literacy state that math, science, and technology are integral parts of scientific literacy. Science involves students in determining reasons for occurrences by carefully observing and trying to fit those observations into a schema to construct meaning. It is also important for students to learn that doing the “same” investigation does not always yield the same results. One reason for this could be differences in procedures used by different groups of students during their investigations. This lesson will address inconsistencies in procedures and will attempt to show students that with careful attention to procedure, investigations will yield reliable, accurate results.

PERFORMANCE OBJECTIVES:

The student will be able to:

Plan and implement simple experiments to determine which brand of paper towel is the “best buy.”
Use tools like mass weights, droppers, measuring spoons, and graduated cylinders to calculate accurate measurements.
Test claims of manufacturers to determine what brand of paper towel stands up to its promotional material.
Communicate in writing and speech the conclusions they have draw and offer support for their conclusions.

RESOURCES:

Paper towels (1 sheet from each of the four brands)
Water
Graduated cylinders (1-25 mL for each group of 4 students)
Gram weights (1 set for each group of 4 students)
Tray (1 for each group of 4 students)

SAFETY CONSIDERATIONS:

Keep your work area straightened to avoid spills
Be careful to clean up all spills especially if the spill is on the floor
Walk during the lab to avoid slipping on wet floors
Do not drink any of the water from the lab

SUPLEMENTARY MATERIALS, HANDOUTS: Handouts (Wet strength test/absorbency data capture sheet handouts for every student) Wet Strength Absorbency

Engagement		Time: 15 minutes
What the Teacher Will Do	Probing Questions	Student Responses Potential Misconceptions
Distribute paper towel wrapper to student volunteers and encourage a discussion about the paper towel qualities.	What brand of paper towel do you use? Why do you think that brand is best? How could you find out for certain that brand is best?	Students will be under the impression that all paper towels are the same.
		Students will think that the only quality of a paper towel is to “pick stuff up”.

Exploration		Time: 5 minutes
What the Teacher Will Do	Probing Questions	Student Responses Potential Misconceptions
Tell the students they will conduct scientific experiments to compare four different types of paper towel brands	How can we keep things fair?	Knowing what the brands are might cause the students to treat them differently, or be biased for or against one or the other.
Divide class into teams of four.	Why might it be good to use letters instead of the actual brand?
Tell students they will work with teammates to devise experiments.
Challenge students to develop a way to conduct their experiments.

Explanation		Time: 5 minutes
What the Teacher Will Do	Probing Questions	Student Responses Potential Misconceptions
Pass out data sheets and have students describe their experiment plan and record results as the experiment progresses.	What are the definitions of wet strength and absorbency?	Students will not all agree on the same definitions for wet strength and absorbency.
Collect data sheets and tell class there will be a discussion of the results next class session.	Are these good definitions?

Elaboration		Time: 15 minutes
What the Teacher Will Do	Probing Questions	Student Responses Potential Misconceptions
Challenge students to find out more ways to test paper towel absorbency and wet strength.	Ask students how they intend to do their experiments.	Students may feel limited in the number of experiments they can do with paper towels.
	Ask students how they will treat all four brands the same, as to be fair.	Students may not know what is meant by “fair”.

Evaluation		Time: 5 minutes
What the Teacher Will Do	Probing Questions	Student Responses Potential Misconceptions
The teacher will pass out a test to assess the students’ knowledge of paper towel strength and absorbency.	Ask students which test is the fairest.	The students may not have been fair in their tests.