GROTON — The fourth-grade classes of Diane Roundtree and Jane Nissi have piloted a unique program highlighting the town’s geology.
After consulting with the teachers, geologist Dr. Nancy Jackson designed and implemented this event to complement the curriculum unit on rocks. Jackson first provided classroom instruction, explaining how glaciers moved from north to south, covering the town under an ice sheet one mile thick.
The students learned how drumlins, eskers and glacial outwash were formed as Jackson used props to help the children visualize these processes.
As the children boarded the bus June 5, they received their own field guides, complete with an overview of the local geology, driving directions to stopping points, open space for notes and diagrams, and empty charts for data from their own hands-on research.
The odd-shaped hills in the center of town took on a greater significance as the glacial origin of the drumlins was understood during the bus ride. Many children live in the Lost Lake area and had no idea their homes were on eskers. Both sides of the bus competed with each other to find the most erratic boulders. Small groups worked together to collect till samples, sorting, measuring and recording the size of the rocks. Raising both hands in the air as the bus bounced over the bumps on Gay Road, students counted the slopes, which are typical features of glacial outwash.
If you need help answering any of these questions, please ask a Prescott fourth-grader for help:
a) What road has curves that are actually the toes of drumlins?
b) How did the big rocks randomly distributed around town get deposited? What are they called?
c) How did Wattle’s Pond form?
d) Did you know that Gay Road’s roller coaster topography is typical of glacial outwash?
e) What direction does the Nashua river flow? Was it always this way?
The final test of the day was easy for these budding geologists. After pulling into the Gibbet Hill parking lot, all the children could determine what direction the glacier moved based on the shape of the drumlins.
This field trip will complement a three-day program for next year’s fourth-graders. Professional development for teachers throughout the district is included in the program, which was funded by the Groton-Dunstable Education Foundation.
The answers to the above questions are:
a) Route 40.
b) Glaciers deposited these large rocks called erratic boulders
c) A glacier formed this kettle pond, which is typically characterized by steep sides and a round shape.
d) Be honest. Your answer is probably no until you read this article.
e) The Nashua river flowed from north to south. When the glacier receded, the ground rebounded from the pressure, elevating to the south. This changed the flow of the water, which now flows from south to north.