Starring:
Cheryl Potocki

"I like to grow things. I'm don't exactly have a green thumb, like my husband, but I like to watch plants -- really look at them at different stages of development," admits Cheryl Potocki. "The farming project has evolved over the last five years, due to grant money for equipment, as well as adding and subtracting different pieces of it."

Although farming might be considered an unusual topic for a math teacher to undertake, the project is just one of many hands-on activities completed by Potocki and her students at The Charter School of Wilmington (Delaware). She designed the project to complement a math course that includes algebra II and pre-calculus, and tackles such topics as polynomial functions, exponential functions, logarithmic functions, trigonometry, statistics, probability, series and sequences, and more.

In the project, students pursue the question, Which method of growing plants do you think is better, organic or conventional (traditional), and why?" First, Potocki's students work online and in the library to find information about different aspects of farming. Their research includes fertilizers, pesticides, herbicides, growth hormones, genetically modified foods, irradiation as a preservation technique, and hydroponics. The students make presentations about the pros and cons of each topic. Then they choose a topic and design an experiment to determine whether organic or conventional growing methods are best.

"For example, a student exploring fertilizer might grow a set of control plants using just a soil medium without any fertilizer added, a set in the soil medium with Miracle Grow added, and a set in an organic soil medium (worm compost)," explained Potocki. "The height and age (in days) of the plants are recorded over four to six weeks. That data is used for statistics and to create different function models for the plants, to determine which model is the best fit."

Though students might be testing different things, their control plants are grown under the same conditions, so the controls can be pooled to form a population they can compare their samples with. Each student can take the z-scores of his test plants and compare the organic to the conventional.

"Each year, the response gets better because each year I have been able to add something to make it run more smoothly -- and also to make it more interesting," Potocki told Education World.

In the past, Potocki's class traveled to Longwood Gardens in Pennsylvania to study growing techniques; this year, students will visit Coverdale Farm, an educational farm run by the Delaware Nature Conservancy. In addition to a close-up view of farming, the site has a few animals, so students can learn about all areas of food production.

"The most important change this year is that I'm working with one of our chemistry teachers, Dr. Rita Vasta, and another math teacher, Mrs. Debbie Ott, to coordinate our math and chemistry classes on a more formal basis," said Potocki. "Now, students go to the farm and take soil and water samples from different fields and water supplies on the farm. In chemistry class, students analyze those samples, thus using the chemistry they learn in context. Then, they do the statistical analysis in math class. We also were able to coordinate topic order in the two classes. Students learn about logarithms in math, and then learn about pH in chemistry."

As students become more adept with lab procedures, they are noticing trends in their sample analysis results, and they've developed more of what Potocki calls a What's next? attitude. Some have been fascinated by how their results in chemistry and math class coincide with what the farmer is actually doing on the farm. Among other discoveries, they've learned that when farmers fertilize crops, they must analyze the soil to determine how many pounds of nitrogen per acre to add.

One of the ways Potocki refines her farming project is through the feedback of students. At the end of the experience, she asks them to share which activities were most effective in building their understanding, and which were the least beneficial. Then she invites them to offer suggestions for improvement.

The eagerness with which her students anticipate their trips to the farm still surprises their teacher. "Most of the kids had never seen a cow before, or heard of crop rotation," Potocki observed. "It's a new adventure for them. On our last trip in February, we were all bundled up climbing around the hills, and my kids were running after a couple of sheep in a pasture. The sheep are due to deliver in the spring, so now my students are eager to go back and see the lambs."

Article by Cara Bafile
Education World®
Copyright © 2006 Education World

04/07/2006