MISCONCEPTIONS OF ROCK FORMATION IN MIDDLE SCHOOL STUDENTS

Rock formation is a key subject taught in earth science classes from middle school through college. Previous research indicates that, after instruction, college students frequently view rocks forming as individual hand samples instead of as part of the bedrock. To learn if middle school students have similar misconceptions about rock formation prior to instruction, we designed four versions of an assessment as part of a larger NSF-funded study through the Rhode Island Technology Enhance Science Project (RITES), asking students about rocks and their formation. Our hypotheses are that if students viewed rocks as forming as hand samples then a) they would include the size and shape of rocks as important characteristics, and b) they would describe rocks’ sizes as a result of forming that size instead of breaking off of the bedrock. We administered questionnaires to sixth grade students (n=39) and eighth grade students (n=60) in different middle schools in Rhode Island prior to instruction about rocks. Analysis of student responses supports the two hypotheses. An example of student responses that supports the first hypothesis is that when asked to list six observations of a picture of a rock, 81% of students answered by describing either shape or size as part of at least one of their comments. An example of student responses supporting the second hypothesis is that when asked a multiple-choice question about how large a sedimentary rock may have been when it first formed, 88% of students indicated that is was the size of a “grape,” “watermelon,” or “desk,” (the most common response was “grape”), and only 8% of the responses correctly chose it was more likely to have formed as the size of “a city.” Our results indicate that many middle school students incorrectly believe rocks form as individual hand samples, with shape and size as important characteristics. This belief prevents students from learning the scientific nature of rock formation and the rock cycle; these misconceptions likely persist upward to the college-level.