Science Model
Paper Towel Testing: Instructional Overview
The teaching strategy for Paper Towel Testing is based on teams of 3 - 4 students working cooperatively to solve a simple problem using a systematic approach of their own design. The problem is to determine which of four common brands of paper towels has the best (a) absorbancy and (b) wet strength. Each of these qualities must first be operationally defined by the team. Then they must proceed to develop a plan for comparing each brand on the trait variable they are testing.
Teams operate like a consumer testing laboratory to rank
order each of the four brands of towels according to absorbancy or wet
strength. Half of the teams assess absorbancy while the other half
assess wet strength. Then each team reports its results. Comparisons
can be made across teams, and consistency of results will be obvious.
This task should require about four sessions. The
first session introduces the question of whether there are variations
in absorbancy and wet strength among different brands of paper towels.
Advertising claims are compared, and personal preferences discussed.
Each team receives a data sheet that provides space for describing the
test and results. Designing a good test can be an overnight assignment.
Performing the tests can take place in the second session.
The second session provides for performing the test and discussing results. Comparing the rankings of each test by anonymous brand letters shows whether different tests yielded similar results. Follow-up experiments can be proposed.
The third session allows for follow-up experiments. Once again the class can see whether one brand of paper towel is consistently "better" in absorbing or remaining strong when wet.
The fourth session brings in cost of purchasing a roll of each brand of paper towels. Cost per sheet is an important construct, since some rolls contain more individual paper towels than others. To determine the "best buy", each team must calculate the cost per sheet and then factor in the relative absorbancy and wet strength.
Each session should end with conclusions and implications for what results say about performance and cost. The final session should conclude with the "so what" question of which brand is the best buy, given the reasons we purchase paper towels. Learners may then inform the grocery shopper in their families as to wise choices from a consumer viewpoint. Sometimes this differs from advertising claims.