Demonstration of software programs for estimating multilevel measurement model parameters.

A brief overview of the relevant parameterizations of the Rasch measurement model will first be provided. Next, the use of five different hierarchical linear modeling software programs (SAS, MLWIN, S-PLUS, R and HLM) using a heuristic data set will be demonstrated. For each program, researchers will be offered: 1) instructions describing the way to set up data sets, as well as 2) directions for running each program, 3) guidelines to assist with the appropriate interpretation of the output. Last, testing of the local independence assumption will be discussed. All data and code for each of the models run in this analysis may be downloaded from the website: http://www.hlm-online.com/papers/mmmpaper.htm/.

Increasing student learning through space life sciences education.

Scientists and educators at Baylor College of Medicine are using space life sciences research areas as themes for middle school science and health instructional materials. This paper discusses study findings of the most recent unit, Food and Fitness, which teaches concepts related to energy and nutrition through guided inquiry. Results of a field test involving more than 750 students are reported. Use of the teaching materials resulted in significant knowledge gains by students as measured on a pre/post assessment administered by teachers. In addition, an analysis of the time spent by each teacher on each activity suggested that it is preferable to conduct all of the activities in the unit with students rather than allocating the same total amount of time on just a subset of the activities.

An approach to improving science knowledge about energy balance and nutrition among elementary- and middle-school students.

Unhealthy diets, lack of fitness, and obesity are serious problems in the United States. The Centers for Disease Control, Surgeon General, and Department of Health and Human Services are calling for action to address these problems. Scientists and educators at Baylor College of Medicine and the National Space Biomedical Research Institute teamed to produce an instructional unit, "Food and Fitness," and evaluated it with students in grades 3-7 in Houston, Texas. A field-test group (447 students) completed all unit activities under the guidance of their teachers. This group and a comparison group (343 students) completed pre and postassessments measuring knowledge of concepts covered in the unit. Outcomes indicate that the unit significantly increased students' knowledge and awareness of science concepts related to energy in living systems, metabolism, nutrients, and diet. Pre-assessment results suggest that most students understand concepts related to calories in food, exercise and energy use, and matching food intake to energy use. Students' prior knowledge was found to be much lower on topics related to healthy portion sizes, foods that supply the most energy, essential nutrients, what "diet" actually means, and the relationship between body size and basal metabolic rate.