This pilot study’s results indicate that PBL has promise in the elementary school classroom. Although some critics (e.g., Dods, 1997; Van den Bossche et al., 2000) suggest that PBL may result in a decrease in content knowledge, that was not the case in this study. The significant growth in the experimental group’s content knowledge and the comparable content test scores in the comparison and experimental groups four months after the teaching of the unit suggest that content knowledge may not be compromised when using PBL