Watch carefully. A little water lands on the bench. Which cloth will soak up more: the paper towel or the tea towel?
How could we find that out fairly, so the comparison is honest?
Our question: Which material soaks up the most water?
Look at the materials we will test. Whisper to your partner which one you think will hold the most water, and say why. Predictions are the start of the science, not a guess to get right.
Five cards are on the board: the material, how much water it holds, amount of water offered, size of each piece, time it sits.
Nobody calls out yet. On your Investigation Journal page, and on your own, write which single card you think is Change and which is Measure. Two minutes, no talking.
Then we place them together and you check your own sheet. Leave what you wrote exactly as it is, even if it turns out differently.

Watch how we measure ml held. Do not write on your journal yet — that starts when your group tests.
Our class method (everyone will use this):
We will do each material twice with a fresh dry piece each time, then find the average.
In your group, test the materials one at a time using the class method on the board. Write each reading on your Investigation Journal page as soon as you measure it — only your group's own trials.
Method every time: same-size dry piece → offer 10 ml → wait 30 seconds → tip the tray so free water gathers, draw it into the syringe, read ml free → ml held = 10 − ml free.
Do each material twice with a fresh dry piece each time, then work out the average. We compare how much each piece holds in 30 seconds, same time for everyone.
If time is tight, finish two materials fully (two dry trials and averages each) and we will pool class data, or cut the set to three materials. Keep the method identical so only the material changes.
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