Boston Children's Museum
308 Congress Street, Boston, MA 02210
Children are inundated with advertisements practically as soon as they are born. Many of these advertisements can be tricky…or even misleading. If we would like our children to grow up to be savvy consumers, we need to help them develop independent thinking skills, and have them practice being thoughtful about the choices that they make. This activity encourages children to compare different brands of products, design scientific tests to compare those products, and determine which of them is the best buy.
When purchasing the facial tissue, be certain to get a range of brands, both some that children have likely heard of (Kleenex; Puff; Scotties; etc.); and some inexpensive brands (such as store brands). If you can find it, you might also try a brand made with recycled paper (such as Seventh Generation). Try to purchase only non-lotion versions. As an alternative, you can ask parents if they are willing to bring in a box of tissues, specifying which brands you would like. Make sure you record the price of each brand, how many tissues are in a box and calculate the cost per tissue. Paper towels also work well for this activity, and will display a more dramatic difference among the brands…but because they are stronger, you will need more weights to test them with.
Tell your students that you have just come from a meeting and a very important decision needs to be made—your afterschool is considering a new brand of facial tissue. Tell them that you would like them to help you make the decision about what brand to buy.
Can you design tests to determine which brand of facial tissue is the best buy?
After each team has designed their experiments and has begun testing, take a break and bring the group together to talk about what they have done so far. Have each team report about what they are testing and how they are conducting their test. As they describe their tests, ask them questions that help them think about how carefully they are testing. Are they stacking the washers or tossing them on? Are they dripping the water onto the tissues in the same spot on each tissue? Ask them why it might be important that they test each brand exactly the same way they tested the others.
Have teams go back to their experiments to finish their testing. Stress the importance of recording their results. Once all tests are done and teams have their results, ask them to assign a score to each tissue brand for each test. The top performer for each test gets a ‘1’, second place gets a ‘2’, third place gets a ‘3’ and 4th place gets a ‘4’. If any brands tie, teams should AVERAGE the two scores…for example, if two brands tie for the best results for strength, one of them would have gotten a 1 and the other a 2…averaging the two yields a 1.5, so they should each be scored with a 1.5. Tying for 1st = 1.5; tying for 2nd = 2.5; tying for last = 3.5. Ask each team to share their scores and record them on a chart. Your chart might look something like this:
|Brand A||3,3,3,4 = 3.25|
|Brand B||4,4,4,3 = 3.75|
|Brand C||2,2,2,1.5 = 1.875|
|Brand D||1,1,1,1.5 = 1.125|
Notice that each of the team’s scores are recorded in the “Strength” column, then the average is calculated. You can ask kids how to find the average of a group of numbers (add them together then divide by how many numbers there were), and maybe even ask them to determine the average themselves. In the chart above, tissue ‘D’ is the winner (the lowest score), followed by ‘C’, then ‘A’ and then ‘B’ scored the worst. Do the same for “Absorbency”, then ask your students if they think that cost is important. Write the word “Cost” in the third column of your chart, and the word “Total” in the 4th column. You can ask the teams to calculate the cost per tissue of the 4 different brands (Cost Per Tissue = total cost divided by number of tissues per box), or you can simply write down the cost. Again, assign each brand a score from 1-4, with 1 being the lowest cost, 4 being the most expensive per tissue.
In the “Total” column, find an average for each brand’s score—add up the scores for Strength, Absorbency and Cost and divide by 3. The brand with the lowest score is the winner!
Ask your kids to name all of the different tissue brands they have heard of, and record them on a piece of chart paper as they list them. Tell your students which 3 or 4 brands you bought and ask them to guess which is which, based on their tests. Reveal the winning brand. Were they surprised by the results?