Description
In the earth sciences, field trips have the potential to provide a foundation for learning concepts that cannot be adequately taught in a classroom. Many ideas that require visualization of spatial relationships between rock units can be addressed in an abstract way in a classroom, but for reasons we do not yet understand, the field environment helps the learner to understand these ideas more deeply. The design of this study is based on evidence that shows that if field trips are conducted without the proper preparation they are not likely to contribute to students’ conceptual understanding of the topic. A curriculum was developed that allowed students to manipulate sediments in order to learn about grain size, transport, and deposition. Three different field trips were administered, one at Torrey Pines State Beach, another at Tourmaline Surfing Park, and a virtual field trip, which was constructed to mimic the Tourmaline field trip. This research was conducted over two semesters in an earth science course for preservice teachers. Students completed assessments at multiple stages throughout the course that measured the progression of their knowledge before instruction, after classroom instruction, and after instruction on an earth science field trip. The instruments tested students’ understanding of sedimentology and change through time. The mid- and embedded tests which were used to evaluate the field trip, tested students’ understanding of the change in depositional environments through time. Results indicate an overall increase in knowledge as a result of the curriculum. According to the matched t-test, students’ post-test scores (M = 26.3 + 5.5) were significantly higher than their pre-test scores (M = 21.2 + 6.9), t = 4.62, p < 0.0001. Item by item analysis reveals that students had prior knowledge of cross-cutting relationships, deltas, ripples, and marine rock assemblages. According to the Wilcoxon signed-rank test, there was a statistically significant difference between students’ scores on the mid-test (M = 3.63, SD = 2.33) and embedded questions (M = 5.29, SD = 1.52), t = 81.5, p = 0.010. Student understanding of changing depositional environments evolved from a static memorization of energy required to transport specific sediment sizes, to a 4 dimensional understanding of change through time as shown in the rock record. This change was a direct result of the field trip. There was no statistically significant difference between the embedded question and mid-test scores according to field trip type, X2 = 1.55, p = 0.460. Generally, students who went on the Torrey Pines (M = 1.83, SD = 1.51) or Tourmaline (M = 2.42, SD = 3.68) field trips showed a greater increase in scores than students who did the virtual field trip (M = 1.21, SD = 2.58). Although the curriculum produced quantifiable gains in low-level, fact-oriented knowledge, a scientifically sophisticated understanding of the relationships between sedimentary environments and their migration over time was demonstrated only after the field trip. Fieldwork contributes to content knowledge and facilitates deeper understanding of geological concepts and should be a regular component of non-majors geoscience education.
