Introducing the Baking Soda Challenge

Watch MOVIE 1 to hear Nancy Cianchetta, 9th-grade science teacher at Everett HS in Massachusetts, as she introduces the Baking Soda design challenge. In this challenge, students are told that a baker needs to make bread but does not have access to yeast. Students will advise the baker to substitute two vinegar and baking soda (acetic acid + sodium bicarbonate) for the missing yeast and while act as consultants will recommend the best recipe (ratio of vinegar and baking soda) for making the bread.

Notice how Nancy frames the challenge without introducing the chemical notion for the reaction. Students' explorations are authentic and qualitative. The products of the reaction are rendered more visible when students put a balloon over the mouth of the flask before the ingredients are mixed. Take note of the small accident that occurs at MOVIE 1's end as a student adjusts the inflating balloon -- how would you handle this Safety issue with your students?

Providing a context for a design challenge, even a fabricated one, is a hallmark of a good design activity. Such contexts are set out in the design brief -- the "you are consultant" gambit is often used, as is the challenge to Design a Toy or game for a user who is younger than the designer. Using a video can also help vividly set the stage for students to address the challenge. For instance, the Learning By Design curriculum uses segments of the movie Apollo 13 to set up the context for doing the Model Parachute and the Vehicles In Motion tasks.