Sachs isn’t looking to bolster her home flower garden with a few free perennials. These shoots are destined for school districts across the region that want to start an ozone garden of their very own.

Sachs wraps the roots in wet paper towels, then a plastic baggie, and carefully packs them in boxes before heading to the priority mail counter at the post office. Students use the coneflowers to track the level of ozone occurring in the environment by observing its effects on the plants, known as bio-monitoring.

“Ozone is invisible. It’s hard to put your mind around something you can’t see,” said Sachs, an education and outreach specialist with the park. “Monitoring the ozone on plants makes the invisible visible.”

Meanwhile, Sachs posts data from the park’s ozone garden on-line, allowing students to compare it to their own data. That’s why schools had to plant an off-shoot of the same plants growing in the park’s ozone garden — so they are comparing apples to apples, or in this case, the same coneflower to the same coneflower.

“With a study you always want to take out as many variables as possible,” Sachs said.

Some schools also post their data on-line, allowing schools to compare their ozone levels to numerous locations.

Most schools that have planted their own ozone gardens have visited the ozone garden on a field trip to the Appalachian Highlands Science Learning Center in the Haywood County portion of the Great Smoky Mountains National Park.

“The idea is they can continue the study back in the classroom by having their own garden and asking their own questions,” said Sachs.

Other times, only the teachers have visited during one of the several teacher workshops Sachs leads at the Learning Center each year. On a few occasions, Sachs has taken the bio-monitoring workshop on the road to further flung school districts, complete with a shoot from the parent coneflower plant to leave with attendees.

Schools participating in the study range from Fairview Elementary in Sylva and Tuscola High School in Waynesville to a school in Washington, D.C.

Participating in a real experiment fits well with the North Carolina science curriculum that includes inquiry-based learning. Students are given tools to ask and answer their own questions, encouraging critical thinking skills.

“Most teachers don’t have the tools they need to do that in the classroom,” Sachs said.

— By Becky Johnson