An exercise to determine the average mass of pennies appears to be in error after students discover a discrepancy in the mass of the coins vs the year minted. Students calculate the densities of pennies and several other metals to identify the composition of past and present pennies. The final lesson uses a time capsule theme as an assessment tool to help students communicate their discoveries about currency to a generation in which paper currency and coins have been replaced by all-electronic transactions. Historical reader and interesting facts about money complete the unit. Materials are sufficient for one class of 32 students working in pairs.
Optional materials needed are heavy-duty clippers, bunsen burner, and tongs.
Students mass the samples and determine the volume of the solids by liquid displacement and the volume of the liquid using a graduated cylinder. All materials except student instructions are reusable. Copyright 2000 Carolina Biological Supply Company. All rights reserved.