I wanted to do a resistance paradigm lab to start the circuits unit in AP Physics 2. I found a Nature of Resistance series of activities from ￼￼the CLASSE Institute for Physics Teachers. The activities seemed well designed and emphasized the connections between macroscopic observations and atomic interactions. Today, after an introduction with an incandescent light bulb and the standard Modeling Instruction paradigm lab discussion, students focused on graphically and mathematically modeling the relationship between resistance and either length or cross-sectional area of the Play-Doh resistor. The accuracy of the data wasn’t fantastic, but they had a lot of fun and saw the relationships among the variables.