Research on learning in the undergraduate chemistry laboratory necessitates an understanding of students' perspectives of learning. Novak's Theory of Meaningful Learning states that the cognitive (thinking), affective (feeling), and psychomotor (doing) domains must be integrated for meaningful learning to occur. The psychomotor domain is the essence of the chemistry laboratory, but the extent to which the cognitive and affective domains are integrated into the laboratory is unknown. For meaningful learning to occur in the undergraduate chemistry laboratory, students must actively integrate both the cognitive domain and the affective domains into the "doing" of their laboratory work. The Meaningful Learning in the Laboratory Instrument (MLLI) was designed to measure students' expectations before and after laboratory courses and experiences, in both the cognitive and affective domains, within the context of conducting experiments in the undergraduate chemistry laboratory. The MLLI was pilot-tested and modified based on an analysis of the pilot study data. The revised, 31-item MLLI was administered online both at the beginning and end of a semester to both general and organic chemistry laboratory students. Evidence for both the validity and reliability of the data, as well as comparisons between general and organic chemistry students' responses, are discussed.

Research on mechanistic thinking in organic chemistry has shown that students attribute little meaning to the electron-pushing (i.e., curved arrow) formalism. At the University of Ottawa, a new curriculum has been developed in which students are taught the electron-pushing formalism prior to instruction on specific reactions—this formalism is part of organic chemistry's language. Students then learn reactions according to the pattern of their governing mechanism and in order of increasing complexity. If students are fluent in organic chemistry's language, they should have lower cognitive load demands when learning new reactions, and be better positioned to connect the three levels of chemistry's triplet (i.e., Johnstone's triangle). We developed a qualitative research protocol to explore how students use and interpret the mechanistic language. Twenty-nine first-semester organic chemistry students were interviewed, in which they were asked to (1) explain a mechanism, given all the starting materials, intermediates, products, and electron-pushing arrows, (2) draw in arrows for a reaction mechanism, given the starting materials and products of each step, and (3) predict the product of a reaction step, given the starting materials and electron-pushing arrows for that step. To investigate the students’ ideas about mechanistic language rather than their knowledge of specific reactions, we selected reactions for the interview guide that had not yet been taught. Following transcription, we analyzed the interviews using constant comparative analysis to explore how students used and interpreted the mechanistic language. Four categories of student thinking emerged with electron movement underlying students’ thinking throughout the interviews. Herein, we discuss these categories, students’ interpretation of the symbolism, connections to learning theory, and implications for teaching, learning, and research.

Meaningful learning requires the integration of cognitive and affective learning with the psychomotor, i.e., hands-on learning. The undergraduate chemistry laboratory is an ideal place for meaningful learning to occur. However, accurately characterizing students' affective experiences in the chemistry laboratory can be a very difficult task. While attitudinal surveys offer some insights, an inherent limitation of such fixed-response surveys may prevent students from expressing how their laboratory experiences shape their affective learning. Conducting interviews, however, affords researchers the opportunity to hear students describe learning in their own words. One challenge with interviews is that students may not possess the vocabulary to precisely describe their experiences. Therefore, the purpose of this study was to conduct interviews that encouraged and enabled students to verbalize their feelings about learning in the undergraduate chemistry laboratory. Interviews were conducted with 13 students who were enrolled in either a general chemistry or an organic chemistry laboratory course using a novel interview protocol to elicit descriptions of the students' experiences: a list of affective chemistry laboratory experiences. Findings include that the list of words was able to elicit a wide range of students' descriptions of their affective experiences and that these experiences influence cognitive and psychomotor learning in the undergraduate chemistry laboratory. In particular, the students' descriptions of their affective experiences in the laboratory were grounded in perceptions of control of their learning and the responsibility they felt they had. The implications of this research include identifying experiences that ought to be attended to through changes in pedagogy and curriculum in order for students to experience meaningful learning in their undergraduate chemistry laboratory courses.

Research on laboratory learning points to the need to better understand what and how students learn in the undergraduate chemistry laboratory. The Meaningful Learning in the Laboratory Instrument (MLLI) was administered to general and organic chemistry students from 15 colleges and universities across the United States in order to measure the students' cognitive and affective expectations and experiences within the context of performing experiments in their chemistry laboratory courses. Data were analyzed using exploratory factor analysis and cluster analysis. The factor analysis revealed unique mental frameworks for how students think about their laboratory experiences. Exploration of the cluster analysis output indicated a four cluster solution for general chemistry students and a three cluster solution for organic chemistry students. The clusters were further analyzed by examining item pre versus post scatterplots to characterize their unique cognitive and affective expectations and experiences for learning. Both courses had a cluster of students with high cognitive and affective expectations that were fulfilled by their laboratory experiences, as well as a cluster of students who had high cognitive expectations but low affective expectations. This cluster's cognitive expectations went unfulfilled, while their negative affective expectations were fulfilled, and their disparate cognitive and affective perceptions created a hindrance for the necessary integration of cognitive, affective, and psychomotor domains for meaningful learning.

Research has shown that within a traditional organic chemistry curriculum, organic chemistry students struggle to develop deep conceptual understanding of reactions and attribute little meaning to the electron-pushing formalism. At the University of Ottawa, a new curriculum was developed for organic chemistry in which students are taught the language of the electron-pushing formalism prior to learning about specific reactions. Reactions are then organized by governing pattern of mechanism rather than by functional group and are taught in a gradient of complexity. To investigate how students are making connections across reactions within the new curriculum, a card sort task was developed. The card sort task consisted of 25 cards, each depicting the reactants and solvent for a reaction taught during the two-semester organic chemistry sequence. The first part of the task asked participants to sort 15 of 25 cards into categories. Then, participants were given the 10 remaining cards to incorporate into categories with the previous 15. Participants were asked to explain the characteristics of each category and their sorting process. Students (N= 16) in an organic chemistry course were interviewed while enrolled in the second semester course. We analyzed the students’ sorts based on which cards were sorted frequently together, the underlying characteristics used to form the categories, and the participants’ sorting processes. Participants created categories based on different levels of interpreting the reactions on the cards, with levels ranging from recognizing identical structural features to identifying similar types of mechanisms. Based on this study, if we want students to develop mechanistic thinking, we think students need to be more explicitly directed to the patterns present in organic reaction mechanisms and given opportunities to uncover and identify patterns on their own, during both summative and formative assessments.