Homework and Academic Achievement in Elementary School Working Paper. Steven McMullen and David Busscher, Department of Economics, Calvin College

In the literature on the impact of homework there is little empirical support for assigning homework to elementary school students. Nevertheless, the practice has become more common, despite popular resistance among many parents and popular media. We examine the effects of both assigning homework and time spent on homework on mathematics and reading achievement using nationally representative longitudinal data on elementary school students. In order to control for important unobserved characteristics and inputs, we use empirical specifications that include student fixed effects. We find that this approach consistently indicates that homework has a positive impact on academic achievement, and that less sophisticated empirical approaches will produce misleading results. Additionally, we find that the impact of homework is not uniform across the population, but that some minority groups and low income students get more benefit from homework, indicating that increasing homework assigned could be a valuable policy for decreasing the black-white as well as the high and low-income achievement gap.

Investigating Student Conceptions of Environmental Systems in a Field-Based Undergraduate Course. Katherine L. Block and Heather L. Petcovic, Western Michigan University, Mallinson Institute for Science Education; Carla M. Koretsky, Western Michigan University, Department of Geosciences

Little is known regarding student conceptions of complex environmental systems and the literature regarding student understandings of biogeochemical cycles and eutrophication is particularly limited. To determine the nature of students' conceptions in this area, we developed a field course for upper level undergraduate Geoscience and Environmental Studies majors in which students engage in problem-based learning, working collaboratively to investigate a real-world environmental system--an urban lake in Kalamazoo, MI.

Data collection included experience, attitude, and knowledge surveys as well as a series of interviews with four of the students in the course. The experience survey examines students' prior courses, research, and relevant work experience. The attitude survey assesses novelty space (comfort and preparation for working outdoors). The multiple choice knowledge survey functions as a pre- and posttest, assessing students' knowledge of eutrophication-related content. The second knowledge survey is a collection of open-ended, higher order, conceptual questions designed to elicit student thinking. Interviews were used to probe students for more detailed descriptions of their understandings of biogeochemical cycling, spatiotemporal heterogeneity, and eutrophication. Student work and interviews were analyzed using qualitative coding methods in order to discern conceptions held by students both before and after completing the course.

In Destitute Places: Religion, Education, and Literacy in the Mississippi Valley 1800-1850. Barton E. Price, Florida State University, Religion Department

This paper uses interdisciplinary methods in the humanities and social sciences to determine the state of cultural and religious "destitution" in the Mississippi Valley during the first half of the nineteenth century. It compares the rhetoric of "destitution" promoted in Atlantic coast periodicals regarding the Mississippi Valley with social scientific data from the 1850 US Census. The findings will determine whether or not the Atlantic discourse about the Mississippi Valley was legitimate. The result is a complicated history of the interaction of America's regions, including the influence of missionary agencies and migrations in the formation of the cultural and religious timbre of the Mississippi Valley.

Folic Acid and Incidence of Birth Defects in Honduras. …