You will need access to water for this activity.

We suggest students work in pairs. Homeschool students can work on their own.

Prepare Mixing Sticks

Break each coffee stirrer in half. Each pair of students will need 5 halves as mixing sticks.

Prepare Cups with Liquids

Gather your plastic 3-oz cups and separate them into two equal piles. Label all cups in one pile "W" and add about 1 tablespoon of water into each cup. Label all cups in the other pile "V" and add about 1 tablespoon of white vinegar into each cup.

Prepare Paper Cups

Gather your paper 3-oz cups and separate them into four equal piles. Label all cups in one pile "B" and add about 1 tablespoon of baking soda into each cup. Label the remaining piles of cups "1", "2", and "3". Then, add 1 tablespoon of each household substance that you'll be testing. We suggest using acidic foods like mustard, ketchup, lemon juice, orange juice, or yogurt. You can also use milk or egg white as less acidic (or basic) substance.

Separate Supplies for Easy Distribution

Students will need supplies at two separate steps of the activity. In Step 2, they will need the following supplies.

Then, in Step 9, they will need the unknown substances and three clean mixing sticks.