Abstract
The purpose of this mixed methods study was to examine the relationship between TAs and students in an inquiry-based undergraduate general chemistry laboratory. Specifically, the investigation sought to understand how a professional development (PD) to support TAs’ implementation of inquiry affected TAs’ chemistry content knowledge, teaching beliefs, and teaching confidence, and how these TA characteristics predicted student outcomes. The study also explored TAs’ practice to characterize the TA-student interactions. The study took place at a mid-sized, public university in the Mid-Atlantic region. Participants included 14 TAs who taught and their 433 students enrolled in the first semester general chemistry laboratory course. The PD experienced by the TAs was informed by this dissertation’s pilot study, situated learning theory, and previous research on PD. The PD occurred during a week-long initial workshop followed by fourteen weekly follow-up meetings. TAs completed pre- and post- PD and end-of-semester (delayed post) surveys that qualitatively and quantitatively assessed their content knowledge, beliefs, and confidence. Six purposefully chosen TAs were interviewed at the beginning and end of the semester to further probe their prior experiences, beliefs, and confidence. Five TAs were observed in the laboratory twice during the semester to characterize their practice. Students completed a multiple choice content assessment on the first and last days of lab (pre- and post- survey, respectively). Quantitative TA data were analyzed using descriptive statistics, non-parametric tests, t-tests and correlations. Qualitative survey and interview data and observations were analyzed using analytic induction (Erikson, 1986). Student data were analyzed using t-tests, correlations, and hierarchical multiple regression. Qualitative and quantitative data analyses revealed some relationships between the professional development and TAs’ content knowledge, beliefs, and confidence. TAs significantly improved their content knowledge from pre- (M=76.02) to delayed-post survey (M=85.20) (p=.01), but no other significant differences existed. Qualitative data suggested TAs held a range of beliefs that were informed by their experiences and were mostly resistant to change. TAs also reported higher confidence in content knowledge than in facilitating student learning. TAs took on similar roles and responsibilities in the laboratory but varied in how they interacted with students. These interactions were informed by TAs’ prior and current experiences and affected the level of student engagement in the laboratory. Student content scores significantly improved from pre-survey (M=52.48) to post-survey (M=73.29) (p<.001) with a large effect size (d=1.7). Student demographics and prior experience were the only significant predictors of student post-survey scores. A case-study comparison of 2 TAs suggested TAs’ content knowledge, beliefs, and confidence related to their practice, and students’ self-reported learning related to their TAs’ practice. This study is the first to connect TAs to student outcomes in the undergraduate laboratory context and proposes that a situated PD may positively impact TAs content knowledge, but may not be sufficient to change TAs’ beliefs and confidence. Future research will further examine the relationship between PD, TAs, and students through the use of varied assessment instruments and investigate how TAs related to the student learning processes.
