Play with a purpose – oobleck

I like to do a pretty light hands-on activity for the first day of school.  Many of you are probably familiar with oobleck (cornstarch and water).  This is a very fun and safe system for students to play with.

This is how I do it:

The hook

Show this video and ask students to think of questions that come to mind:

Freeze the video at the appropriate point to generate discussion (I like to do this before the guy in the lab coat lets himself sink into the oobleck pool).  Ask students to write down as many questions as they can in 2 minutes and tell them not to share their questions with each other yet.  After the 2 minutesis up, give them another 2 minutes to share with a neighbor.

Now, you need to call on a few students to gather a list of questions.  Do not evaluate the questions (I always get quite a few about the program being in Spanish, or things like “why are we watching this”).  Once you have a decent list (say, 5-10), ask the students which one they want to answer.  I usually try to make sure that “is is real?” is somewhere on the list and that we are trying to answer that question (maybe along with one of their choice).  This is a good point to talk about skepticism.

Play with a purpose

Next, tell the students to grab a cup, a popsicle stick and some cornstarch.  Ask them to play with it by adding water and trying to find an interesting consistency.  Tell them to be observant and to get their hands dirty.  It’s time to “play with a purpose.”  Remind them that their purpose is to use their observations to decide if the video is real or not!

Once most of the students have a good mixture, I like to take them outside and let them really play with it.  I tell them to pour it, try to form it into a ball, throw it on the ground and see what happens, etc.

Argument based on evidence

Back inside the classroom now, I ask what the answers to our questions were.  I ask, “was the video real?” and get a resounding “YES!”  I ask the students how they know and they tell me that they just DID it – and some of them will describe how the oobleck behaved.

Now I tell the students that they just did science.  They played with materials but did so with a purpose – to answer a question with evidence.

Then we watch the rest of the video and enjoy the goofiness of it togther.  Invariably some kid asks, “can we do that?”

I wish kid, I wish…


Play with a purpose

play with a purpose

play with a purpose

During last week’s scichat (#scichat) on Twitter, I mentioned, “play with a purpose.”  Play with a purpose is a saying that I often use with students.  It means checking out something new in a systematic way; having fun in an organized fashion; discovery with a goal.

Play with a purpose activities are opportunities for students to discover and explore something that you hope will inspire inquiry.  It is a way to guide inquiry while still doing open-ended inquiry.  It is also a good way to assess inquiry skills.

The idea of play with a purpose is that you give students something – an object, a set of chemicals, an organism, a system – and ask them to see what they can find out about it.  I usually ask them to record their findings in a t-chart of observations vs. questions.  Of course, you must clearly identify any safety hazards prior to this activity.

After play with a purpose, students should have a lot of questions and thoughts generated that they can use to create a scientific question that they want to answer.

Some examples of play with a purpose activities I’ve done with students:

  • combine cornstarch with water and see what happens [fluid dynamics, macromolecules, polymers, non-Newtonian fluids]
  • observe stoneflies (they do pushups when the dissolved oxygen level in their water gets low) [homeostasis, gas exchange, physiology, respiration, etc.]
  • mix Alka-Seltzer with water in a closed film canister and observe the resulting explosion [reaction kinetics, acid/ base chemistry]
  • make whirligigs [gravity, aerodynamics]
  • vinegar and baking soda [acid/ base chemistry, gas production, reaction kinetics, etc.]
  • dilute HCl and various materials [metals, wood, plastics, etc.]
  • bromothymol blue, calcium chloride, and baking soda [endothermic/ exothermic reactions, reaction kinetics, etc.]

Let’s pick one and see where it goes, shall we?

Prior to an inquiry investigation into the effects of different parameters on reaction rates, I have students play with alka seltzer and film canisters.  I demonstrate one and require all to wear safety goggles.  I then give them the materials and step back and observe.  I answer no questions, except those related to safety.  They play with the stuff, manipulating variables haphazardly to see what happens.  They jot down observations and questions.  After a period of this, they are ready to generate a scientific question and design experiments.

The learning target that is posted on the board during these activities: “I can play with a purpose”

Photo credit: Keven Law http://www.flickr.com/photos/kevenlaw/2961840972/ used under cc license