Secret Formulas: Making Toothpaste

We have finally finished making our secret formulas of toothpaste. The kids had to choose how much of each ingredient to add, based on the testing we had done. Each ingredient (calcium carbonate, a mixture of 3 parts baking soda to 1 part salt, glycerin and soap {Ivory Snow}) has strengths and weaknesses and they had to choose how much of each ingredient to add based on which qualities (taste, texture, sudsing ability, cleaning ability) meant the most to them. They also had a lot of flavors to choose from. We just used regular McCormick's flavorings (coconut, cinnamon, peppermint, lemon, vanilla, chocolate to name a few). No sweeteners of any kind were added.

Fifth Student writes down what he has put in.

Fifth student product tests.

The results are that none of them were ready to turn in the store bought toothpaste for their own creations, but they had a better understanding about what factors go into making a good toothpaste.



Related Posts:
Secret Formulas: Paste
Secret Formulas: Cola Taste Test
Secret Formulas: How Sweet IS Coke?
Secret Formulas: To Each His Own Cola
Secret Formulas: Ice Cream
Secret Formulas: Toothpaste
Secret Formulas: Testing Cleaning Ability

Source:
GEMS Guide Secret Formulas Grades 1–3 
Students eagerly investigate the properties of substances as they make their own personal brands of paste, toothpaste, cola, and ice cream. The activities have been designed to convey key science/mathematics skills and concepts, provide motivating real-life experiences with chemistry, and build comprehension of cause and effect, central to later understanding of controlled experimentation. Secret Formulas speaks to the need expressed by many primary school teachers for more high-quality physical science activities.