Icebreaking Activity: Mystery Tubes

Today was my first day with the elementary kids.  This is a brand-new school with about 22 students total in grades 1-6, and there is flexibility to work with age-segregated or mixed-age groups.  I did the mystery tube activity (with extension #1) because it's a good icebreaker, and it naturally comes first because it addresses the nature of science.  (By the way, I discovered this activity when the folks from http://undsci.berkeley.edu/ came to UC Davis and conducted a workshop on science outreach.  Their website is worth a look, especially the diagram showing the real process of science, which is the exact opposite of the cookbook 5-step procedure you see in most textbooks.  But maybe that's another post.)

I chose mixed-age groups because I was afraid the younger kids would struggle with it, and could use assistance from the older ones (the activity is recommended for grades 6-16, but I was pretty confident that grades 4-6 could handle it well).  There was a fair amount of awkwardness because everybody was new to the school, and there was no established pattern of working in groups; some students still didn't know some other students' names!  Considering that, it seemed to go fairly well.  While some younger kids did struggle, a few other younger kids just nailed it. So while I still wouldn't recommend it for a group younger than 4th grade, it was eye-opening to see some really good results from individual 2nd-graders.  At the same time, I have to admit that there wasn't much discussion of concepts like "Test results sometimes cause scientists to revise their hypotheses."  We were doing those concepts, but it was hard to discuss them in these mixed-age groups.  In the future, if I have mixed-age activities I might think about how to "debrief" the older kids separately afterward, to discuss how they can take what they learned in the activity and generalize it to make it useful in other parts of their studies and their lives.

A few tips for those wishing to do this:

• have a bucket of threadable beads ready.  These are handy for tying onto the strings in the models so they don't slip through the holes in the toilet paper tubes, as well as for connecting the strings in the interior (in any way they wish; I don't hint in any way that they should use the beads to connect the strings, but they get used because they're handy).

• I made tubes with different types of connections in the interior, because often when two groups of scientists think they're doing the same experiment, they're not really, due to some confounding variable.  So I think having all tubes identical subverts the process-of-science aspect of the lesson, and this came in really handy when students begged me for the answer (I honestly didn't know the answer for each individual tube) or thought they figured out the answer and tried to tell everyone else rather than let the others experiment more.
• If you suspect groups might not function well as a group, it's ok to forget about "sharing findings" and the like. I wish I had more toilet paper tubes because many students wanted to make their own model, and I think that would have been better than forcing students to build models in groups. It's hard to wait for your turn at improving the model! 
• We did it in 3 rotations of 20-25 minutes each.  I think it needs a bit more time than that, like 30 minutes.

Update: it may not have been clear why I don't want to tell them the answer. The activity is a miniature version of the process of science.  Students build and refine a model of how the tube works.  In the same way, when scientists build and refine a model of how the Sun works, for example, there is no way to reveal the correct answer.  They can only think of better and better ways to test the model, and improve the model if any test shows a problem with it.

Most discussions of the process of science focus on the mechanics of it.  Students pose a question ("How does this thing work?"), suggest hypotheses (saying "I think there's a knot inside" and drawing a diagram of where and what kind of knot), and then test their hypotheses ("If I pull here it should...").  This is all great, but teachers usually present it in a context where the correct answer is already known, or revealed at the end.  If the answer is already known ("today we will measure the density of water"), the activity turns into a dry, dull exercise.  If the answer is revealed at the end, the whole idea of science as an ongoing process of inquiry is subverted.