Freestyle Barbie Bungee – No Steps Required

After completing day 1 of the infamous Barbie Bungee activity I look on my twitter to see the the following tweet from @ddmeyer:

How many different ways can a popular lesson (Barbie Bungee) go wrong? Extremely provocative post from @mathhombre. bit.ly/ULssnB

— Dan Meyer (@ddmeyer) February 2, 2013

Even though it is only Day 1 of the experience of our 3 day activity, I want to respond to @mathhombre and share what is happening in my Grade 8 class.

Goal:
In 3 math classes, you and your bungee company will take your first customer to the drop point, letting them fall over the side and experiencing the most exhilarating moment of their plastic doll life. Your job is to determine the right length of the bungee cord that will create the best fall. Good Luck!

With only the above goal, my class has started their 3 day (no worksheet) activity to get their Barbie closest to the floor. The students were given only two things to guide them. One is the outline of what is happening and the other is a graphic organizer to help them break down their large question into smaller, simpler ones that they are able to answer. Divided into groups of 3 or 4 with a barbie, ruler, meter stick and 10 rubber bands they have a day to create a plan that will help them determine how many rubber bands they will need to create the best fall for their barbie. As explained in the outline, they have no idea what that height is until the drop day and they aren’t allowed to drop their barbie if they don’t have a logical and well thought out explanation that includes data to support their ideas. To help those that may get stuck I created scaffolding questions that could be given depending where they were being challenged and needing support. I also created a worksheet just in case groups became too lost and frustrated that the overall goal was not being met.

The three days are broken down as follows:

Day 1:

• Collect your materials (barbie, 10 elastics, ruler, metre stick)
• Create a plan in how your group will determine the final number of rubber bands for the drop day.
• Ensure that you are thinking of how to collect DATA as evidence for your proposal.

Day 2:

• Write a proposal for your company answering the question of How do you know the approximate number of rubber bands needed to drop the barbie from a height.
• The proposal will explain why you know the number of rubber bands based on the data you have collected in the previous class.
• When given the test height, use your proposal to determine the number of rubber bands. Make the cord and test it in the secret location. You are not allowed to guess and check for the test drop day.

Day 3:

Drop Day

My students will test their ideas and are required to write a proposal on the test drop day, alter their plans accordingly and drop them next Wednesday. After this we will be sharing how each group created their plan and explain their method with the class. My hope is that each group will write out their plans/formulas/calculations/tables on chart paper and post them around the room. As a class they will do a gallery walk to find similarities and differences between their own methods and others. We will also explore which methods worked better than others and ask why that was.

From this I plan on launching into the linear relations unit by associating vocabulary with their methods . For example:

• Some students were creating a table of values but didn’t know that is what it was called or various ways to create one.
• Another group was determining how much further the Barbie would drop with each added rubber band but didn’t know that this is the rate of change.
• Other groups were debating which central tendency (mean,median,mode) would be the most valuable one to use in the situation for their test trials (which they determined they needed).

The students bring with them and understanding of percentages, finding patterns and creating an equation to represent a pattern but all within structured standard questions. I am hoping (fingers crossed) that this unstructured activity will give them a starting point to explore and identify what is important in a problem, how to measure it and if there is anyway that they can use their results to make a prediction. We also will be exploring what makes a prediction valid and how to question if it will work in various situations.

I have no idea if any of the groups will save their Barbie’s brains or allow them to have a great fall, but already with the lack of structure of history of working through similar problems they automatically directed themselves to the steps and processes a worksheet would have done. I just feel that a structured worksheet directions would not have made them ask the following questions which were heard today:

• Should we measure the weight of the Barbie? I know that in Science we have to do that thing with gravity and weight.
• If there are 6 centimeters from the Barbie’s head to the floor with one meter, will it double when we double the height and number of rubber bands or will it stay the same?
• Are all the elastics the same size and thickness and pre-stretched the same amount like my jeans?

I wasn’t planning on posting until the end of the process, but after @mathhombre’s comments, I wanted to share that we are testing this very idea over the next few days.

I hope that you will check in and see how things progress next week. I will also be thinking about where to take the group next and posting their created proposals to show the diversity of what they were able to come up with on their own and without coaching.