What is it? The Story of Oobleck
Lesson 5 of 15
Objective: SWBAT identify a mystery substance as either a liquid or solids using prior knowledge and claim, evidence, reasoning.
Teacher Tip: This lesson is a fun opportunity for students to apply their knowledge of liquids and solids to a physical object. You will need to prepare the Oobleck substance for the students ahead of time. Although, if you have more time, you could have them prepare it themselves by following a procedure. I chose to prepare it for them in the interest of time, waste and mess conversation. To make Oobleck follow the recipe in this link. Prep time for this lab was about 20 minutes for me, making 4 Oobleck samples. This lesson involves the students designing a plan to test the substance and executing this plan, thus addressing NGSS SP3.
To start the lesson, students will work on recalling their knowledge of liquids and solids by responding to the following in their student notes sheet.
This is when the fun starts! Students get an opportunity to experience the Oobleck and make their observations. Place the containers on their table. Tell them it's not poison, so it won't hurt them when they touch it, but they shouldn't eat it and should be careful not to spill or get any on their clothing. Always make sure there are ample paper towels for each table in order to immediately clean any messes- it's not the easiest substance to clean!
Students will make observations and will be guided in doing so by the prompts on their student notes sheets:
There is a mystery substance, called Oobleck, in the container on your tables. It is your job to find out what kind of matter Oobleck is- liquid? or solid?
Make observations by answering the questions below.
What does it look like?
What does it feel like?
What happens when you pour it?
What happens when you squish it?
After 7-8 minutes, I will make sure the students have made their observations and their space is being cleaned up. The next 3-5 minutes should be spend reflecting and actually writing their responses to the questions above.
The students will now reflect on their initial observations and write a "hypothesis" about which state of matter Oobleck is- liquid or solid- base on their observations. Students are generally confused during this part and really are town between liquid and solid- they should be! Oobleck is a non-Newtonian fluid which means it behaves like more than one form of matter. The point here is for students to make a claim and support it with evidence. They may be rather convicted in their choice, or they may say it's both liquid and solid. This answer is fine, as long as it's supported with evidence from their observations. In this student sample the student chose to explain how oobleck is a liquid.
Next, provide the students a chance to test the Oobleck in a way that will help them to prove their claim or begin either liquid or solid. Five minutes should be spent exploring the substance and the remaining 5 will be spent responding to the prompt below:
Perform any test you want to the Oobleck. Write down your observations below. Use the evidence to support your reasoning in your final conclusion.
We tested the Oobleck by…
We found out…
After the time is up, I will ask a few groups to share their responses in order to give more support for other groups.
This last section is for student to really iron out their claims with supporting details. Here is where they should be making a final claim and supporting it. This writing should be done in their notes sheet in response to:
Use all of your evidence to make your final claim about Oobleck. Is it a solid? Is it a liquid?
According to my observations, Oobleck is a…
I know this because when I…
Oobleck and (solids/liquids) are similar because…
I know it’s not a… because…
The sentence starters are helpful here for those students who find the process of writing daunting or difficult. It gives them a chance to see the structure of the paragraph before they begin, helping them to organize their thoughts.