This research presents an investigation of how students dynamically construct knowledge in a new situation. In particular, this work focuses on the contexts of light and optics, and examines the dynamic construction of an understanding of wavefront aberrometry. The study began with clinical interviews designed to elicit students prior knowledge about light, basic optics, and vision； the data were analyzed phenomenographically to obtain student models of understanding and examine the possible model variations. The results indicate that students have a significant number of resources in this subject area, though some are incomplete or less useful than others. In subsequent phases, many learning and teaching interviews were conducted to design and test scaffolding procedures that could be of use to students as they constructed their understanding of the given phenomenon. Throughout this work, student responses were analyzed in terms of the resources that were being used through the knowledge construction process. Finally, a modified analysis method is presented and utilized for quantifying what types of concepts students use while constructing their understanding, and how they are able to link varying types of concepts together. Significant implications extend beyond the single context of wavefront aberrometry. Each distinct analysis technique provides further insight to the ways in which students learn across contexts and the ways in which we can scaffold their learning to improve curriculum and instruction.

The purpose of this study is to find out what students in the first chemistry course at the undergraduate level (general chemistry for science majors) know about the affordances of instrumentation used in the general chemistry laboratory and how their knowledge develops over time. Overall, students see the PASCO(TM) system as a useful and accurate measuring tool for general chemistry labs. They see the probeware as easy to use, portable, and able to interact with computers. Students find that the PASCO(TM) probeware system is useful in their general chemistry labs, more advanced chemistry labs, and in other science classes, and can be used in a variety of labs done in general chemistry. Students learn the affordances of the probeware through the lab manual, the laboratory teaching assistant, by trial and error, and from each other. The use of probeware systems provides lab instructors the opportunity to focus on the concepts illustrated by experiments and the opportunity to spend time discussing the results. In order to teach effectively, the instructor must know the correct name of the components involved, how to assemble and disassemble it correctly, how to troubleshoot the software, and must be able to replace broken or missing components quickly. The use of podcasts or Web-based videos should increase student understanding of affordances of the probeware.

Instructors of physics often use examples to illustrate new or complex physical concepts to students. For any particular concept, there are an infinite number of examples, thus presenting instructors with a difficult question whenever they wish to use one in their teaching: which example will most effectively illustrate the concept so that student learning is maximized? The choice is typically made by an intuitive assumption about which exact example will result in the most lucid illustration and the greatest student improvement. By questioning 583 students in four experiments, I examined a more principled approach to example selection. By controlling the manner in which physical dimensions vary, the parameter space of each concept can be divided into a discrete number of example categories. The effects of training with members of each of category was explored in two different physical contexts: projectile motion and torque. In the first context, students were shown two trajectories and asked to determine which represented the longer time of flight. Height, range, and time of flight were the physical dimensions that were used to categorize the examples. In the second context, students were shown a balance-scale with loads of differing masses placed at differing positions along either side of the balance-arm. Mass, lever-arm length, and torque were the physical dimensions used to categorize these examples. For both contexts, examples were chosen so that one or two independent dimensions were varied. After receiving training with examples from specific categories, students were tested with questions from all question categories. Successful training or instruction can be measured either as producing correct, expert-like behavior as observed through answers to the questions) or as explicitly instilling an understanding of the underlying rule that governs a physical phenomenon. A students behavior might not be consistent with their explicit rule, so following the investigation of their behavior, students were asked what rule they used when answering questions. Although the self-reported rules might not be congruent with their behavior, training with specific examples might affect how students explicitly think about physics problems. In addition to exploring the effectiveness of various training examples, the results were also compared to a cognitive theory of causality: the contingency model. Physical concepts can often be expressed in terms of causal relations e.g., a net force causes an object to accelerate), and a large body of work has found that people make many decisions that are consistent with causal reasoning. The contingency model, in particular, explains how certain statistical regularities in the co-occurrence of two events can be interpreted by individuals as causal relations, and was chosen primarily because it of its robust results and simple, parsimonious form. The empirical results demonstrate that different categories of training examples did affect student answers differently. Furthermore, these effects were mostly consistent with the predictions made by the contingency model. When rule use was explored, the self-reported rules were consistent with contingency model predictions, but indicated that examples alone were insufficient to teach complex functional relationships between physical dimensions, such as torque.

Students with blindness and low vision BLV) have traditionally been underrepresented in the sciences as a result of technological and attitudinal barriers to equal access in science laboratory classrooms. The Independent Laboratory Access for the Blind ILAB) project developed and evaluated a suite of talking and audible hardware/software tools to empower students with BLV to have multisensory, hands-on laboratory learning experiences. This dissertation focuses on the first year of ILAB tool testing in mainstream science laboratory classrooms, and comprises a detailed multi-case study of four students with BLV who were enrolled in high school science classes during 2007–08 alongside sighted students. Participants attended different schools； curricula included chemistry, AP chemistry, and AP physics. The ILAB tools were designed to provide multisensory means for students with BLV to make observations and collect data during standard laboratory lessons on an equivalent basis with their sighted peers. Various qualitative and quantitative data collection instruments were used to determine whether the hands-on experiences facilitated by the ILAB tools had led to increased involvement in laboratory-goal-directed actions, greater peer acceptance in the students lab groups, improved attitudes toward science, and increased interest in science. Premier among the ILAB tools was the JAWS/Logger Pro software interface, which made audible all information gathered through standard Vernier laboratory probes and visually displayed through Logger Pro. ILAB tools also included a talking balance, a submersible audible light sensor, a scientific talking stopwatch, and a variety of other high-tech and low-tech devices and techniques. While results were mixed, all four participating BLV students seemed to have experienced at least some benefit, with the effect being stronger for some than for others. Not all of the data collection instruments were found to reveal improvements for all of the participating students, but each of the types of data sets provided evidence of benefit for varying subgroups of participants. It is the expectation of the ILAB team that continuing to implement adaptive/assistive technologies for BLV students in science laboratory classrooms will foster enhanced opportunities in science classes and professions.

Part I. Among room temperature ionic liquids RTILs), those derived from the imidazolium cation are the most common. RTILs have generally been viewed solely as solvents, but they are able to participate in certain types of reactions, particularly due to the relatively high acidity at the imidazolium C2. Deprotonation affords N-heterocyclic carbenes NHCs), which can cause unwanted side reactions. Consequently, the major limitation of imidazolium RTILs is that they cannot be used as solvents in highly basic reactions such as the Baylis-Hillman and Grignard reactions. This work reveals a convenient route for the preparation of C2-substituted imidazolium ionic liquids. This method involves the alkylation of N-heterocyclic carbenes, which are readily generated from the C2-unsubstituted imidazolium ionic liquids. It works well for nonfunctionalized alkyl chlorides and less well for alkyl bromides and iodides, likely due to competing elimination reactions. The resulting C2-substituted salts can be transformed into ionic liquids via standard anion metathesis reactions. Part II. Recent advances in media and the increasingly encyclopedic nature of traditional textbooks have made their role in college classes uncertain. In an effort to discover what is really being taught in organic chemistry courses across the US, a survey of organic chemistry professors in all 50 states was conducted to determine what material is covered in their organic chemistry courses for science majors. Survey Monkey, an online survey program, was used to construct a short 10-item survey which was sent to organic chemistry professors at various types of institutions across the nation. We sent out 2417 surveys and received 489 responses. The results of this survey revealed what topics the professors believe is core material and what they feel is extraneous. Additionally, this research identifies the things these professors would like to see changed in the organic chemistry texts. From the open-ended portion of the survey data, an analysis of organic chemistry textbooks was created. Books were analyzed for number and types of problems, number of example problems, and number of problems containing answers in the back of the book. The analysis of the thirteen books revealed there was a statistically significant difference between the books in number and types of problems. This work will reveal the findings of the analysis.

We designed and implemented curriculum intended to be used by students in an algebra-based introductory physics laboratory course. Our curricular goal was to foster, through observations in the lab, a coherent framework in students understanding of general principles presented in the introductory mechanics course, while addressing known student difficulties. The research that guided our curriculum development efforts, however, was previously implemented in an intervention setting which was quite different from ours, and was conducted on students enrolled in calculus-based physics courses who were generally academically better prepared than our students. We describe the development of laboratory materials, designed to fit the specific curricular constraints of a lab course at NMSU. We present some results from post-testing of our labs, which were not as favorable as results obtained by researchers at other institutions implementing similar curricula in their courses. We attempted to quantify differences in preparation among our introductory physics student populations who use these laboratory materials. We developed a short proportional reasoning pretest, which we found to be a relatively efficient predictor of student success in our courses. We investigated the effect of context variations on performance by various student populations on this pretest, and found that the effect of context variation was not the same for all of our student populations. Results from our calculus-based population showed a small but significant increase in performance when we modified the context of our pretest, while the performance of our algebra- based population showed very little sensitivity to the variation in pretest context. Finally, when considering students gender, we found in both algebra-based and calculus-based physics courses that female students were significantly affected by context variation, while male students performance remained relatively unchanged when we varied our pretest context.

Research-based instructional methods are applied in an effort to close the persistent gender gap in physics. Creating a short text on a limited topic using some of these methods could benefit female students specifically. A literature review showed research on the gender gap in physics and updated instructional methods for females. Two female physics students were interviewed and observations were conducted at a high performing all-girls school. A physics lab dialogue between two female physics students was recorded and analyzed, which informed the style and voice of the interactive dialogue lesson. An original written lesson intended to engage female physics students was created and tested on three classes of college-level physics students. The survey data, based on multiple choice and essay responses, measured the students’ opinions of the lesson and their current textbook. Results showed the interactive lesson was preferred over the current text, and some students requested similar lessons.

Students often make errors when trying to solve qualitative or conceptual physics problems, and while many successful instructional interventions have been generated to prevent such errors, the process of deduction that students use when solving physics problems has not been thoroughly studied. In an effort to better understand that reasoning process, I have developed a new framework, which is based on the mental models framework in psychology championed by P. N. Johnson-Laird. My new framework models how students search possibility space when thinking about conceptual physics problems and suggests that errors arise from failing to flesh out all possibilities. It further suggests that instructional interventions should focus on making apparent those possibilities, as well as all physical consequences those possibilities would incur. The possibilities framework emerged from the analysis of data from a unique research project specifically invented for the purpose of understanding how students use deductive reasoning. In the selection task, participants were given a physics problem along with three written possible solutions with the goal of identifying which one of the three possible solutions was correct. Each participant was also asked to identify the errors in the incorrect solutions. For the study presented in this dissertation, participants not only performed the selection task individually on four problems, but they were also placed into groups of two or three and asked to discuss with each other the reasoning they used in making their choices and attempt to reach a consensus about which solution was correct. Finally, those groups were asked to work together to perform the selection task on three new problems. The possibilities framework appropriately models the reasoning that students use, and it makes useful predictions about potentially helpful instructional interventions. The study reported in this dissertation emphasizes the useful insight the possibilities framework provides. For example, this framework allows us to detect subtle differences in students reasoning errors, even when those errors result in the same final answer. It also illuminates how simply mentioning overlooked quantities can instigate new lines of student reasoning. It allows us to better understand how well-known psychological biases, such as the belief bias, affect the reasoning process by preventing reasoners from fleshing out all of the possibilities. The possibilities framework also allows us to track student discussions about physics, revealing the need for all parties in communication to use the same set of possibilities in the conversations to facilitate successful understanding. The framework also suggests some of the influences that affect how reasoners choose between possible solutions to a given problem. This new framework for understanding how students reason when solving conceptual physics problems opens the door to a significant field of research. The framework itself needs to be further tested and developed, but it provides substantial suggestions for instructional interventions. If we hope to improve student reasoning in physics, the possibilities framework suggests that we are perhaps best served by teaching students how to fully flesh out the possibilities in every situation. This implies that we need to ensure students have a deep understanding of all of the implied possibilities afforded by the fundamental principles that are the cornerstones of the models we teach in physics classes.

There are far fewer high school students enrolled in physics than in chemistry or biology courses within the province of Alberta (Alberta Education, 2007). Students are also completing the highest level math course in larger numbers than those taking physics. It appears that a fear of physics exists within students in our province； this fear seems to be related to a level of difficulty the students associate with physics. Many students either opt to not take physics or enter the course with the expectation of failure. In this study I explored the impact of physics’ reputation upon a group of students who chose not to take physics. In addition, I attempted to determine whether the perception of the difficulty of high school physics is accurate. This was done by investigating the perceptions of several students who took physics. I surveyed students from one high school in a small urban school district using group interviews. The students were in grades 10 to 12 and divided into groups of Science 10, Physics 20 and Physics 30 students. The students were interviewed to gain a deeper understanding of what perceptions they have about physics and why they may have them, hoping to identify factors that affect their academic decision to take or not take physics classes. For the students interviewed, I found that the biggest influence on their decisions to take or not take physics was related to their future aspirations. The students were also heavily influenced by their perceptions of physics. The students who took physics claimed that physics was not as difficult as they had believed it to be and they reported that it was interesting, enjoyable and relevant. Those students who had chosen to not take physics perceived it would be difficult, irrelevant and boring. Therefore, a major difference of perception exists between the students who took physics and those that did not.

The emergence of embodied cognition as a theory of learning has placed new emphasis on the interdependent relationship between what the mind perceives and what the body experiences. Movement and objects in the physical environment take on significant roles in the process of learning within this view and the role of gesturing in cognition has become increasingly interesting. Significant research suggests that the physical process of gesturing is connected to how the mind processes information. Gesturing during the recall of information is a universally known phenomena and one that seems to aid in the process of recall. More recent findings have suggested that the use of gestures may play a helpful role in assisting learners with processing information and particularly with retaining information longer. This study investigates this claim by using intentional gestures at the time of encoding new information to assist a group of first year chemistry students in high school process how to identify and label Lewis acids and bases in reaction schemes. A treatment group received an intervention lesson where key concepts were instantiated with the use of related gestures while the control group received the same lesson without the use of gestures. The intervention lesson involved students using BeSocratic, a web-based, interactive system currently under development. Performance was assessed with a pre-post test and a delayed post-test administered three weeks after the intervention to determine if the treatment group would retain the concepts significantly better than the control group. The results showed that two groups of students with similar backgrounds in the material exhibited similar gains in information from the intervention lesson. However, when given the same assessment three weeks later, the group of students who had received the gesture enhanced lesson significantly outperformed those students who did not. The gains were limited to questions most directly linked to the gestures. The results are part of a small but growing body of evidence that suggests that the use of gestures during the encoding of new information does offer a tool to help learners retain information.