Toward Interdisciplinary Learning: Development and Validation of an Assessment for Interdisciplinary Understanding of Global Carbon Cycling

Abstract

This study developed and validated an assessment that measures interdisciplinary understanding using the topic of carbon cycling, the Interdisciplinary Science Assessment for Carbon Cycling (ISACC). This work was motivated by the need to assess interdisciplinary understanding, defined as the ability to solve problems requiring knowledge and skills from multiple disciplines. Levels of a construct map for interdisciplinary understanding were generated and refined in the construct-modeling design process (Wilson 2005). Key concepts in carbon cycling to be assessed were determined based on experts’ concept maps and analysis of the Next Generation Science Standards. The final version of the ISACC includes 11 multiple-choice (MC) items and eight constructed-response (CR) items covering nine key concepts. Of these 19 items, six are single-disciplinary items and 13 are interdisciplinary items. Four hundred fifty-four students in grades 9–16 were recruited and administered the ISACC. For the CR items, scoring rubrics were developed and used by a group of evaluators to code student responses. Two item response theory models, a two-parameter logistic model and a generalized partial credit model, provided evidence of the construct validity of the items. All items reflected unidimensionality and local independence and showed moderate internal consistency (Cronbach’s alpha = 0.782). All except one were a good fit to the models. The findings suggest that the ISACC is a promising tool to assess interdisciplinary understanding of carbon cycling. Future directions include research into test fairness across gender and ethnic/racial groups and further development to cover typical high school students’ knowledge more thoroughly.