SAND OR SILT AT THE DESERT OF MAINE: A STUDENT-CENTERED PROJECT ALIGNED TO NEXT GENERATION SCIENCE STANDARD PERFORMANCE EXPECTATION 5-PS1-3

The Desert of Maine is an anthropogenic disturbance set in a several hundred-acre deposit of sand in the northwestern portion of Freeport, Maine. The deposit accumulated from actions of post-glacial-retreat winds, probably from between ~12,700–12,000 years ago, at which point pathfinder plants stabilized it. Farming practices in the late 19th century caused the deposit to become partially re-exposed and worked by historic winds, resulting in the dramatic dune field which persists to this day. Though large and spectacular, the Desert has received little research attention. This has allowed misinformation to perpetuate in the popular press, including a notion that the dune field is silt rather than sand. During a Fall 2020 course at the Desert (taught by Smith), interest in the sand/silt problem led to a student-centered (by Suzuki) grain-size analysis of dune field material in hopes of generating results to help counter the misinformation. Because the Next Generation Science Standards (NGSS) are silent on specifically when core content related to rock and mineral identification should be taught, this project was aligned to NGSS Performance Expectation 5-PS1-3 (make observations and measurements to identify materials based on their properties), which seems a logical solution to the deficiency. We sampled five locations in the dune field. Equivalent volumes of each sample were weighed and then sorted using six Titan 9cm sieves, making observations and producing data in accordance with the practice of 5-PS1-3 and the standard units aspect of its crosscutting concept. Suzuki compared the separations to a standard Wentworth grain-size scale, addressing relevant aspects of the crosscutting concept and core idea. We graphed the data and he presented them to his classmates. This preliminary analysis indicates that the dune field is dominated by medium and fine sand and is demonstrably not silt. A student-centered investigation, this project involved applying all three dimensions of an NGSS Performance Expectation to an interesting real-world problem, and in doing so generated scientifically relevant results.