Size and scale curricular activities for middle school

CHED 1615

César Delgado, delgadoz@umich.edu, Shawn Y. Stevens, sstevens@umich.edu, and Joseph S. Krajcik, krajcik@umich.edu. School of Education, University of Michigan, 610 East University Avenue, SEB4031, Ann Arbor, MI 48109
Understanding size and scale is a key prerequisite for learning chemistry at the nanoscale. Our research reveals that middle and high school students have fractured and incomplete conceptual understandings of size. Based on our research on student understanding and motivation, curricular activities designed to foster understanding of size were developed for a two-week middle school summer science camp. We identified key ideas, and contextualized the activities so they would be relevant to students. An inquiry approach was used in the activities. Activities included: pre and post focus group discussions to establish baseline knowledge and learning gains; measuring with invented and SI units; an exploration of the nature of linear and logarithmic number lines; representing the number 1 million, and the fraction 1/1000; length to volume scaling; and examining and modeling the effects of surface area to volume ratio – a key nanoscience concept. Students had statistically significant learning gains on the written test; qualitative analysis of small group discussions further characterized the nature of the students' learning.