You will need access to water for this activity.

Each student will make their own hat, but groups of four students will share a cup of water for the Sweat-Soaker test.

Prepare Supplies

• Cut a 3-foot length of string/yarn/ribbon for each student.
• Tear off a 9” piece of aluminum foil for each student.
• Fill each cup about halfway with water.
• Optional: Provide a hand-held mirror so students can see their hats as they work on them.

Engineering Teacher Tip

We created the Hat Inspiration printouts for students who are stumped and frustrated by the task of making a hat. We suggest letting students try building on their own first, then providing these Inspiration Sheets only to those who may need additional help.

We suggest students work in pairs and share water bottles in table groups of four. Homeschool students will need a partner for this activity.

You will need access to hot water for this activity. You can fill bottles an hour or two ahead of class if you have a cooler (or a cardboard box and a bath towel) to keep the water bottles hot.

Prep Aluminum Foil

Tear aluminum foil into 10” squares. Each pair of students (or each homeschool student) needs two 10” squares.

Fill the Plastic Bottles

Each group of four students (or homeschool student) needs two plastic bottles. Half of the bottles will be filled with cool or cold water and the other half will be filled with warm or hot water. The difference in temperature between the two bottles has to be enough to feel easily with bare hands. You can use ice water and warm water or you can use very hot water and cool water. You just need to make sure there is a definite difference.

You can keep your hot bottles hot (or your cold bottles cold) for a couple of hours if you put them in a cooler or in a cardboard box with bath towels as insulation.

Each student will create their own paper tower, but we suggest students work in pairs to share ideas.

Each student will need a flat, level area where they can build a tower without bumping into someone else’s. Desktops and tables are great. Floor space works as long as you have a hard surface. We don’t recommend building towers on a carpet.

We suggest students work in pairs. You will need access to water for this activity.

Prepare Dixie Cups

Divide your Dixie cups into three equal piles. Use a marker to write “A” on each cup in one pile, write “B” on each cup in the second pile, and write “C” on each cup in the third pile.

Add 2 teaspoons of cornmeal into each cup that is labeled “A.” This is a model for sandy soil.

Add 2 teaspoons of flour into each cup that is labeled “B.” This is a model for clay soil.

Add 1 teaspoon of flour and 1 teaspoon of cornmeal into each cup that is labeled “C.” Gently shake these cups to mix the cornmeal and flour together. This is a model for a mix of sand and clay soil.

Prepare Water Cups

Fill each Solo cup about a quarter full of water. Each pair of students will only need a few spoonfuls.

Teacher Tip

Making a mud model is very fun, but it can also be distracting! We recommend waiting to distribute the cups of water and spoons until Step 5 of the activity, after students have explored the dry soil models.