This project was created to use a real-world application of empirical formulas that students investigate during their first year of high school chemistry. As do many of my creative ideas, this lesson’s theme popped into my head one summer day while I was working in my backyard where I grow mint, bee balm, lemon verbena, basil, rosemary, sage, and many vegetables. I have always been intrigued by the folklore, ancient medicinal uses, and herbal applications of the plants that I have successfully cultivated in a northeast Ohio urban setting.
Students further their understanding of empirical and molecular formulas by investigating herbal remedies. Many students may drink ginger ale when they have an upset stomach and recognize the connection to the herb ginger root. Students may be frustrated at first to realize that there is no empirical formula for ginger root, so you have to guide them to investigate the chemical compounds that are in ginger root, or other herbal remedies. Students should be encouraged to look for those compounds’ chemical formulas.
As I brush past the sweet smelling mint or the savory odor of bee balm in my garden, I am reminded of teas or foods that these herbs can add flavor to. As the first group of students who were given the assignment discovered, the knowledge of herbal remedies is addicting. The more I learn, the more I want to know. And almost every student’s research paper ended with, “I have really enjoyed learning about this herb,” or something very similar.
For the project, I allow five days of classroom instruction. On day one, I give students a model presentation, using a PowerPoint, about green tea. During the presentation, I emphasize that I don’t read directly from the slides, so students begin to understand what a good presentation looks like. I distribute the project outline and explain the three graded components of the project: a paper, a poster, and the presentation. The full lesson is available in the AACT classroom resource library.
Students choose topics to research using books I check out from the library, such as Herbal Remedies Handbook by Andrew Chevalier or Heinerman's Encyclopedia of Fruits, Vegetables & Herbs by John Heinerman. During the second and third class days, students conduct research on their topic (plant/herbal remedy) and outline and write their research paper in a five-paragraph format. Most students choose to work on their posters and presentations at home, but you could provide supplies in class for students to create their posters during class time. And if they have limited computer use at home, they could create their presentations during class. On days four and five, students present. They may bring in samples of their herb or plant to share with classmates.
At the end of my sample presentation, I serve them green tea. On a cold winter’s day, having a “tea party” in chemistry class may be memorable, but the interest that is piqued through all of the senses is priceless—visual (PowerPoint), kinesthetic (moving around, preparing and drinking tea), auditory (oral presentation)—and is worth every effort on my part.
Teaching for me has always been about sharing my love and enthusiasm for science. Students are empowered to learn during this lesson and begin to see a glimmer of what the big picture may be. The chemistry that is shared may lead to healthy lives for my students, and that is an added bonus.
Photo Credit: Depositphotos.com/aragami12345 (Top), Depositphotos.com/duskbabe (Bottom)