How to teach properties of matter

Why this matters

A student can watch water soak into cotton and still pick cotton for a raincoat, because soft is the property he already knows. On a worksheet the water test and the choice are separate boxes, so nothing connects them, and the teacher has to wait for quiz day to find out.

Properties of matter

A property is something students can observe or test about a material, such as its color, texture, hardness, flexibility or how much water it soaks up. Students first describe and sort materials by the properties they observe (NGSS 2-PS1-1). Then they use test results to pick the material that suits a job best (NGSS 2-PS1-2). An absorbent material soaks up water, so it suits a towel. A waterproof material keeps water out, so it suits a raincoat.

In the Flint activity, each student presses Drop Water on six materials in the Material Sort, sees whether the water soaks in or rolls off, and drags each material into an absorbent or a waterproof bin. Then the student picks a material for a raincoat for their own pet. On a worksheet, the test and the choice sit in separate boxes. When a student picks cotton because it's soft, Sparky asks what the water did on the cotton card, so the student uses their own test result to choose again.

Leo picks a raincoat for Biscuit

Leo has a dog named Biscuit who likes soft things. Leo can tell soft from hard, but he hasn't used the words "absorbent" or "waterproof", and he hasn't used a test result to make a choice.

Every student in the class gets the same greeting and the same Material Sort: six materials to drop water on and sort into two bins. The rest of the chat is each student's own. Sparky puts the student's pet into its questions, and its next message depends on what the student just said.

Sparky uses Leo's dogSparky sends Leo back to his own testA right answer gets a harder question

L

Leo

Interest: His dog, BiscuitStarting point: Knows soft and hardGets stuck: Picks the softest material for every job

Sparky

Hi there, scientist! Today you're going to help your pet stay dry in the rain. First, what pet do you have, or what pet would you love to have? And what's their name? Then press Drop Water on every card in the Material Sort and drag each card into the right bin.

Leo

i have a dog named biscuit

Leo

done! it says all sorted

Sparky

Great job sorting! Which material would you pick to make a raincoat for Biscuit? Why?

Leo

cotton because its soft and biscuit likes soft stuff

Sparky

Aww, that's sweet that Biscuit loves soft things! What happened when you pressed Drop Water on the cotton card? What did the water do?

Leo

it soaked in

Sparky

Right! The water soaked in. What would happen to Biscuit if his raincoat soaked up all the rain?

Leo

he would get wet and cold. so not cotton. plastic! the water rolled off it

Sparky

Yes! The water rolled right off the plastic! When water rolls off, we call that waterproof. When it soaks in, we call that absorbent. Should Biscuit's towel be made of plastic too? Why or why not?

Leo

no! the towel has to soak up the water to dry him. so cotton for the towel

Understanding check

Cotton is absorbent, just right for drying Biscuit off! What other property matters for the raincoat, besides keeping water out? Think about foil vs. rubber.

Leo

it has to bend so biscuit can run. foil is stiff and crinkly. plastic bends

Sparky

Biscuit needs a raincoat that's waterproof and bends, so plastic is perfect! Here's Biscuit in his shiny plastic raincoat.

Picked cotton, went back to his water test, chose plastic, then explained the towel

Leo is an example student, and Sparky's replies are shortened. The Material Sort picture shows the sort partway through, while the wet spots still show.

What Flint did for Leo

• Sparky's greeting gave Leo the Material Sort, where he dropped water on six materials and sorted them himself.
• Sparky put Biscuit into the raincoat and towel questions after Leo named him.
• When Leo picked cotton because it's soft, Sparky asked what the water did when he tested the cotton, and didn't give him the answer.
• Once Leo picked plastic, Sparky named the two properties he had tested, then asked whether Biscuit's towel should be plastic too.
• Sparky drew Biscuit in the plastic raincoat Leo chose.

A teacher can't do this by hand for 30 students at once. Sparky does it in every student's chat.

The activity page shows who picked a material that soaks up water

While students work, Needs attention lists each student who is stuck and the message that showed it. Once three or more students submit, activity analytics sums up what the class understood and what to practice next.

Set up the activity for free

Pick the Right Material is in Flint's public library, with the Material Sort, the greeting, Sparky's guidelines and a rubric already set up. Open it, duplicate it into a free Flint account, and assign it to a class. Every student gets their own chat with Sparky and their own Material Sort, and the activity page fills in as they work.

For more science activities, see Flint for science.