This lesson introduces properties in which to sort materials and the profession of material engineers. Students consider what is a measurable test.
2-PS1-1 Plan and conduct an investigation to describe and classify different kinds of materials by their observable properties.
Students sort materials by flexibility, hardness, and absorbency. Students discuss and provide examples how certain properties of materials are suited for different purposes.
- Asking Questions and Defining Problems (SP 1)
Students ask which material best show different properties and ask how they can test the material to show how well the material exhibits a given property.
- Planning an Carrying Out Investigations (SP 3)
Students plan an investigation to test materials for a certain properties.
Cross-cutting Concepts - Appendix G
- Structure and Function (XC 6)
Students explore how a material's properties lend itself to different functions.
Select the properties that you would like to explore with your students. I chose flexibility, hardness, and absorbency.
These are terms that are used to classify materials. I wanted to expose students to other property terms beyond, shape, color and texture.
Set up the demonstration lab to show how tests can be measurable (see section: material engineers discuss procedure)
1 material tub per team
Set up the material tubs, placing at least 3 items / property
I chose material that exhibited the properties to varying degrees so that materials could be ranked.
Print the lab booklet. I chose to run it one sided in case teams needed more room to write.
Pull out the property page and make extra copies to correspond with the number of properties your students will be testing.
My students tested for 3 properties, so each lab booklet would need 3 of the property pages.
Put together lab booklets for each teams
Decide how the teams will be set up
Make a map for team stations
Possible materials to test for each tub:
flexibility - 5 pipe cleaners taped together, card stock with same dimensions as a ruler, plastic ruler
hardness - limestone rock, granite, popsicle stick
absorbency - sponge, paper towel, school paper towel
other possible materials: 5 straws taped together, CD's, pencils, legos, straw
Science starts with a question, usually written on the board. This allows students time to consider today's topic before the lesson has officially begun. I have established this routine with the kiddos to keep transition time short and effective and redirect student's attention back to content while allowing time for focused peer interaction.
Question for the Day: What is an example of a flexible material? hard material? absorbent material?
I have posed this question to assess what my students understand about the property vocabulary and to develop their schema for the term 'material'.
Before students turn and share their ideas to today's question, I point to the science terms on the KLEWS chart to review our definition of matter. "The words matter and material are synonyms. Today's question asks about material, which is matter. Please read the question. "
Students have worked with synonyms during 'word study' time.
"Materials can have many properties. Flexibility, hardness and absorbency are just a few properties of matter. These properties are words that can be used when describing solids."
I want to make the connection to previous learning when students compared solids and liquids.
"Please turn to your shoulder partner and discuss what materials may have one of these properties."
When students have turned toward me, their signal that they have finished their discussion, I call on volunteers to share their examples which I write under the property heading. I use this opportunity to clarify any misconceptions about the property vocabulary.
For example, one of the answers was a desk. We discussed how this is made from a number of materials. I explained that the desk was a product made from different materials.
Introducing Material Engineers
"There are scientists who test materials for different properties, they are called, materials engineers. For example, NASA needs to be able to build rockets that are light and strong. So the material engineers will choose and test materials to help engineers decide which materials should be used to build the rocket."
"Can you think of someone else we learned about this year that probably worked with material engineers to build his craft? Yes, James Cameron, who built a submersible to dive to the Marinas Trench."
"For the next 2 science labs you will be materials engineers. Selecting materials for the properties you discussed and testing materials to see just how flexible, hard or absorbent a material is."
Overview of the Lab
"There will be 2 phases to your lab today. First you will sort and choose 3 materials for each property of hardness, absorbency, and flexibility.
Then we will brainstorm the criteria for each property. If the property you are testing for is hardness, what is the criteria that lets us know it is hard? The property criteria you choose will help you plan how you to test your materials."
I use the 'random sorter' to establish the lab teams and direct teams to sit at their assigned lab station. While students move to their lab tables, I pass out a tub with materials to be sorted.
"Materials engineers, you have a couple of minutes to explore what is in your material tub, while I pass out your lab paper."
The kiddos have been sitting for awhile, allowing them to handle and explore the materials in an unstructured atmosphere, gives them a chance to connect with their team members and become familiar with what is in the tub.
After teams are settled and checking out the materials in their tubs, I pass out the lab paper.
I signal for students' attention and direct them to place all the materials back in the tub.
"Let's review the property names before you sort out your materials."
I project the property and definition. I invite students to read the property and definition. As a class, we review the list of materials students shared during the 'question of the day', to see if the materials meet the definition.
Taking time to review the property definitions, ensures that there is a common conceptual base from which students can start their discussions.
After the terms are reviewed, teams sort materials for the given properties and select their top 3 materials to test for each property.
"After your team has selected the top 3 materials, a team member will list the materials for that property on your lab paper. Next, with your team, discuss which material will show the property the best and write your hypothesis."
If students ask, I let them know that it is o.k. to select the same material for another property if the team feels like that is one of the top 3 materials that shows that property.
As teams collaborate to choose their top 3 materials that represent a given property, they are beginning to discuss the criteria, which will be addressed later in this lesson.
After teams have selected their top 3 materials for each property, I invite them to the rug.
Moving the students to the rug, removes the distraction of the materials that are on their desk.
"As material engineers, we have a problem to solve. What is our problem?" Yes! Which material shows the property the best?"
"Now that your material engineering teams have selected the top 3 choices for the properties of hardness, absorbency, and flexibility, we need to collaborate on the criteria that you will use to test your material."
"Hmm, materials engineers how will you test for these properties? What criteria will you use to test the material?"
"For example when you tested the 'mystery matter' to see if it was a liquid, you thought about the criteria for what made a material a liquid, like if it should take the shape of its container."
"Then you planned tests to see if it would act like a liquid. So if you want to test a material to see how flexible it is, then your test should show the flexibility of the material."
"I think this would be a good time to review our definitions so that we can think about what criteria you could use to test for the different properties."
I project the definitions that I had up earlier. I write student criteria ideas on the referenced slide.
I start by showing students that we can pull criteria words from the definitions.
"What words in the definition help us know the criteria we should test for?" I circle the words students state.
For each property I help the students scaffold the criteria they will reference when planning their tests.
Possible criteria to discuss with the students:
Flexibility - bend without breaking, ability to return to its original shape once the stress have been removed;
Hardness - resists scratching or denting
Absorbency - soaks up the liquid, feels dry
Encouraging students to participate with establishing the criteria provides an opportunity to model how to approach a problem scientifically.
"Now that the criteria has been set for each property, when I say go, teams will move back to their stations and discuss how you could test the materials for the property criteria."
"This is a brainstorming session. I want you to only discuss one property test. You will have about 5 minutes to discuss before I signal for your attention."
I check that each property will be discussed. If not I will ask for a volunteer team to discuss a different property. I want the teams to explore how they could set up one procedure, having them focus on one property allows for a more in depth discussion.
The kiddos have been working hard to develop the testing criteria. At this point they need a change in pace. Sending them back to their station gives them an opportunity to handle the materials again and talk with their team.
I walk around the room to listen to students' ideas. I scaffold conversations to lead students to think how they could set up a test where the criteria can be measured. I plan to use this discussion to lead into the next section.
I signal for team's attention and direct them to place all the materials in the tub.
"I heard some great ideas, I would like to share what this team was thinking about."
Depending on discussions I hope to showcase a team that explains how they can measure for one of the criteria. If not, I may start a discussion like this:
"You job is to test for the property criteria to find out which material shows the best absorbency, flexibility or hardness. To help make your results more reliable, so someone else could do the test and get the same answer, it helps to set up a test where the property can be measured and then someone else could do the test and see of they get the same measurements."
"It is easier to compare materials when you use numbers versus comparative words such as the brick is stronger than the wood. This does not show how much stronger, what if there were 2 types of wood?"
"Material Engineers plan tests that help them measure the property criteria. For example, to test which material is strong, the engineer could place weight on top of one of the materials and see how much it will hold before it breaks. Then the engineer would have this data to write in their observations.
I use two different types of paper folded into thirds. These are taped and spanned across two boxes. I place a cup on each one and add pennies. I show how the strength can be measured and recorded.
"Show me with your thumb if the idea of setting up a measurable test makes sense."
"Show me with your thumb if you have some ideas how you could set up a measurable test for the property criteria?"
I want to get an idea if students are following the discussion. This may be a stretch for my little ones.
"Please discuss your testing ideas with your teams. Keep in mind that the supplies you may need for your property test should be things we can find in the classroom or at home."
I listen to conversations and help guide teams to consider tests that can be measurable.
After teams have discussed some ideas for how to test for the 3 properties, I signal for students' attention. I invite teams to share their ideas on testing the materials and note their ideas on the Smartboard. As students share their ideas, I help scaffold the testing so that it includes a measurable test.
Their ideas will be reviewed in the next lesson.
"Thank you for all your focused discussions today! When we meet next for science you will plan your tests."
"One person from each team will keep your lab book in his or her science folder. Please place your material tub on the back counter."