Cognitive development and problem solving of Afro-American students in chemistry

The aims of this study were to investigate the level of cognitive development of Afro-American students enrolled in general chemistry courses at the college level and to determine the strategies used by both successful and unsuccessful Afro-American students in solving specific types of stoichiometric problems. It was found that the choice of a strategy is not significantly related to cognitive development of the student in specific types of stoichiometric problems. However, the following trend was noted: Students who are formal-operational in thought are more likely to be successful when solving mole-volume problems and complex mole-mole problems than are their concrete-operational counterparts. Additionally, a systematic strategy proved to be successful for the students, regardless of the cognitive development, when balancing simple and complex chemical equations. Also, algorithmic/reasoning strategies were needed to solve the mole-volume problem. A higher level of cognitive development and reasoning may be crucial factors in solving the more sophisticated types of problems in stoichiometry.     

Multiple-choice exams: an obstacle for higher-level thinking in introductory science classes

Learning science requires higher-level (critical) thinking skills that need to be practiced in science classes. This study tested the effect of exam format on critical-thinking skills. Multiple-choice (MC) testing is common in introductory science courses, and students in these classes tend to associate memorization with MC questions and may not see the need to modify their study strategies for critical thinking, because the MC exam format has not changed. To test the effect of exam format, I used two sections of an introductory biology class. One section was assessed with exams in the traditional MC format, the other section was assessed with both MC and constructed-response (CR) questions. The mixed exam format was correlated with significantly more cognitively active study behaviors and a significantly better performance on the cumulative final exam (after accounting for grade point average and gender). There was also less gender-bias in the CR answers. This suggests that the MC-only exam format indeed hinders critical thinking in introductory science classes. Introducing CR questions encouraged students to learn more and to be better critical thinkers and reduced gender bias. However, student resistance increased as students adjusted their perceptions of their own critical-thinking abilities.     

Reasoning strategies used by students to solve stoichiometry problems and its relationship to alternative conceptions,prior knowledge,and cognitive variables

Achievement in science depends on a series of factors that characterize the cognitive abilities of the students and the complex interactions between these factors and the environment that intervenes in the formation of students' background. The objective of this study is to: a) investigate reasoning strategies students use in solving stoichiometric problems; b) explore the relation between these strategies and alternative conceptions, prior knowledge and cognitive variables; and c) interpret the results within an epistemological framework. Results obtained show how stoichiometric relations produce conflicting situations for students, leading to conceptual misunderstanding of concepts, such as mass, atoms and moles. The wide variety of strategies used by students attest to the presence of competing and conflicting frameworks (progressive transitions, cf. Lakatos, 1970), leading to greater conceptual understanding. It is concluded that the methodology developed in this study (based on a series of closely related probing questions, generally requiring no calculations, that elicit student conceptual understanding to varying degrees within an intact classroom context) was influential in improving student performance. This improvement in performance, however, does not necessarily affect students' hard core of beliefs.     

Statistics using just one formula

This article advocates that introductory statistics be taught by basing all calculations on a single simple margin‐of‐error formula and deriving all of the standard introductory statistical concepts (confidence intervals, significance tests, comparisons of means and proportions, etc) from that one formula. It is argued that this approach will better emphasize the core concepts and commonality of statistics and range of statistical applications, without forcing the students to memorize lots of different equations.     

Could HPS Improve Problem-Solving?

It is generally accepted nowadays that History and Philosophy of Science (HPS) is useful in understanding scientific concepts, theories and even some experiments. Problem-solving strategies are a significant topic, since students’ careers depend on their skill to solve problems. These are the reasons for addressing the question of whether problem solving could be improved by means of HPS. Three typical problems in introductory courses of mechanics—the inclined plane, the simple pendulum and the Atwood machine—are taken as the object of the present study. The solving strategies of these problems in the eighteenth and nineteenth century constitute the historical component of the study. Its philosophical component stems from the foundations of mechanics research literature. The use of HPS leads us to see those problems in a different way. These different ways can be tested, for which experiments are proposed. The traditional solving strategies for the incline and pendulum problems are adequate for some situations but not in general. The recourse to apparent weights in the Atwood machine problem leads us to a new insight and a solving strategy for composed Atwood machines. Educational implications also concern the development of logical thinking by means of the variety of lines of thought provided by HPS.     

Implementation of a project-based molecular biology laboratory emphasizing protein structure-function relationships in a large introductory biology laboratory course

In introductory laboratory courses, many universities are turning from traditional laboratories with predictable outcomes to inquiry-inspired, project-based laboratory curricula. In these labs, students are allowed to design at least some portion of their own experiment and interpret new, undiscovered data. We have redesigned the introductory biology laboratory course at Brandeis University into a semester-long project-based laboratory that emphasizes concepts and contains an element of scientific inquiry. In this laboratory, students perform a site-directed mutagenesis experiment on the gene encoding human γD crystallin, a human eye lens protein implicated in cataracts, and assess the stability of their newly created protein with respect to wild-type crystallin. This laboratory utilizes basic techniques in molecular biology to emphasize the importance of connections between DNA and protein. This project lab has helped engage students in their own learning, has improved students' skills in critical thinking and analysis, and has promoted interest in basic research in biology.     

Cognitive strategies used by chemistry students to solve volumetric analysis problems

The study investigated the strategies used by 47 high school students to solve volumetric analysis problems in chemistry. Using the talking-aloud technique, the students were required to calculate the concentration of hydrochloric acid used in a titration with NaOH after having performed the titration themselves. Students were met individually and their verbalization audiotaped. After making this calculation, each student was asked to use the same data to predict the concentration of acid in three situations involving different mole ratios. It was found that two main strategies, Formula Approach and Proportional Approach with their variants, were employed by the students during the problem solving process. The Formula Approach was found to be used mainly by the students in the high ability group while students in the low ability group used the Proportional Approach. It was also found that problems involving 2:1 stoichiometric ratios presented a number of conceptual problems to the students. These conceptual problems were found to be related to their inability to write balanced equations or write correct formulas, focusing on only the strength of acid, inability to use the mole ratios in the calulations and deriving the mole ratios from the formulas of reactants.     

Students' Studying and Approaches to Learning in Introductory Biology

This exploratory study was conducted in an introductory biology course to determine 1) how students used the large lecture environment to create their own learning tasks during studying and 2) whether meaningful learning resulted from the students' efforts. Academic task research from the K–12 education literature and student approaches to learning research from the postsecondary education literature provided the theoretical framework for the mixed methods study. The subject topic was cell division. Findings showed that students 1) valued lectures to develop what they believed to be their own understanding of the topic; 2) deliberately created and engaged in learning tasks for themselves only in preparation for the unit exam; 3) used course resources, cognitive operations, and study strategies that were compatible with surface and strategic, rather than deep, approaches to learning; 4) successfully demonstrated competence in answering familiar test questions aligned with their surface and strategic approaches to studying and learning; and 5) demonstrated limited meaningful understanding of the significance of cell division processes. Implications for introductory biology education are discussed.     

The Challenge of College Youth

The problem of motivation has received a great deal of attention, and many successful approaches have been developed. However, in areas such as introductory college mathematics, students often question their own potential for success. At the first sign of trouble, their fears are confirmed and many of them drop out, formally or informally. If a method could be found to improve persistence, motivational techniques would have an opportunity to succeed. In this article, the author describes a simple method to improve persistence using assessments that are normally already in place. Data are presented indicating that the method improves persistence and achievement.     

Enhancing Student Motivation and Learning: Experiences with a Simple Simulation

This paper examines the author's experiences in an introductory course in international relations with a simple simulation. The objective is to encourage others who have not yet done so to try using a simple simulation. After a brief review of the literature on simulations, it shows how the simulation is an easy and effective way to motivate students, improve social relations among students, and enhance learning. By participating in the simulation, students gain insights from their personal experiences. They gain insights into some of the problems confronting foreign policy makers and into the essence and limitations of the dominant approach to the study of international relations which provides the underlying assumptions upon which the simulation rests. Because it is a simple simulation it is easy to use early in an introductory course, but its very simplicity means it must not be used later in the course when a more complex simulation would be required. The paper encourages others to try simple simulations and makes some general observations for easy, early and effective use of them.     

A model for teaching an introductory programming course using ADRI

High failure and drop-out rates from introductory programming courses continue to be of significant concern to computer science disciplines despite extensive research attempting to address the issue. In this study, we include the three entities of the didactic triangle, instructors, students and curriculum, to explore the learning difficulties that students encounter when studying introductory programming. We first explore students’ perceptions of the barriers and affordances to learning programming. A survey is conducted with introductory programming students to get their feedback on the topics and associated learning resources in the introductory programming course. The instructors’ perceptions are included by analyzing current teaching materials and assessment tools used in the course. As a result, an ADRI based approach is proposed to address the problems identified in the teaching and learning processes of an introductory programming course.     

Some reflections upon teaching Sociology at a distance

This article reviews an introductory sociology course taught at a distance. After an outline of the course structure, the major teaching strategies adopted are discussed with an emphasis upon those which seek to foster sociological understanding by requiring students to explore links between their own social experience and the sociological concepts, theories and methods to which they are being introduced. Results from an evaluation study of students’ responses to these teaching strategies are also discussed.     

University Students’ Conceptualization and Interpretation of Topographic Maps

This study investigates the strategies and assumptions that college students entering an introductory physical geology laboratory use to interpret topographic maps, and follows the progress of the students during the laboratory to analyze changes in those strategies and assumptions. To elicit students’ strategies and assumptions, we created and refined a topographic visualization test that was administered before and after instruction to 26 students during the first semester of the study and to 92 students during the second semester. To more deeply understand how students think about and conceptualize topographic maps, we focused on eight individual students who were interviewed about their pretest and posttest answers as well as videotaped during three laboratory sessions. We found that even students who claim never to have worked with topographic maps often perform impressively on their pretests by making useful assumptions about symbolic topographic information. Some students, however, begin with less productive assumptions that may be unfamiliar to some instructors (e.g., thinking that the spacing of contour lines indicates elevation instead of slope). Initial success should not be misinterpreted, however, as an integrated understanding of topographic maps. Only in posttest interviews do most students express explanations integrating multiple normative assumptions. In addition to highlighting the strategies and assumptions that college students use to interpret topographic maps, we outline the implications of these findings for the design of learning objectives, curricular activities, and assessments for topographic lessons in introductory college geology courses and the training of future geoscientists.     

浅谈语言自主学习中心的管理

建立一个为广大学生服务的自主学习中心需要有明确的目标、先进的理论指导和配套的软硬件设施。但是,当前我国许多自主学习中心较为普遍的存在着硬件设备不足、管理水平低下、学生认知策略和认知策略缺乏等问题。因此,对中心工作人员分门别类地进行培训,对学生在入学初进行中心的介绍与培训是提高中心服务能力和质量的重要措施。     

Using real data for statistics education in an open‐source learning environment

The tutor‐web is an open‐source learning environment designed to be used for teaching mathematics and statistics. The system offers thousands of exercises at high school and university level, and has been used for a decade to teach introductory statistics courses with good results. A new component has recently been added to the tutor‐web so that students can enter their own data or get real data from several data sources for practicing and learning new concepts.     

1, 2, 3, 4: Infusing Quantitative Literacy into Introductory Biology

Biology of the twenty-first century is an increasingly quantitative science. Undergraduate biology education therefore needs to provide opportunities for students to develop fluency in the tools and language of quantitative disciplines. Quantitative literacy (QL) is important for future scientists as well as for citizens, who need to interpret numeric information and data-based claims regarding nearly every aspect of daily life. To address the need for QL in biology education, we incorporated quantitative concepts throughout a semester-long introductory biology course at a large research university. Early in the course, we assessed the quantitative skills that students bring to the introductory biology classroom and found that students had difficulties in performing simple calculations, representing data graphically, and articulating data-driven arguments. In response to students'' learning needs, we infused the course with quantitative concepts aligned with the existing course content and learning objectives. The effectiveness of this approach is demonstrated by significant improvement in the quality of students'' graphical representations of biological data. Infusing QL in introductory biology presents challenges. Our study, however, supports the conclusion that it is feasible in the context of an existing course, consistent with the goals of college biology education, and promotes students'' development of important quantitative skills.     

LONG LIVE TRADITIONAL TEXTBOOK PROBLEMS!?—CONSTRAINTS ON FACULTY USE OF RESEARCH-BASED PROBLEMS IN INTRODUCTORY COURSES

Though many research-based problem types have been shown effective in promoting students’ conceptual understanding and scientific abilities, the extent of their use in actual classrooms remains unclear. We interviewed and surveyed 16 physics and engineering faculty members at a large US Midwest research university to investigate how university instructors value and use different types of problems in teaching their introductory courses. Most of these instructors valued traditional textbook problems as a useful building block and used them frequently. They also valued non-traditional problems but seldom used them in their introductory courses. The divergence between value and use in part is due to limited resources and experience, time constraints, student reactions, and personal preferences. It is, however, also due to the fact that the beliefs held by some instructors regarding the nature of problem solving deviate from commonly accepted views in educational research. Although on average instructors were hesitant to reduce more than 20 % of course content for research-based materials, they showed great interest in collaborating with educational researchers at a more personal level to increase the use of non-traditional problems in teaching. Our study indicates that instructors need not only research-based problems suitable for their introductory classes, but also assistance in how to effectively implement these problems.     

Hey,HPT practitioner! Talk to me

It is important to clearly articulate what the essence of human performance technology (HPT) is about. Too often we are caught in our own jargon and confuse our clients and jeopardize appropriate outcomes. A group of graduate students in an introductory HPT class responded to an assignment to explain to other professionals what human performance practitioners do. Their thoughts, written in their own voices, are reflected here.     

大学生情绪管理与压力应对

大学生情绪管理是对大学生个体的情绪进行控制和调节的过程,它是研究大学生对自身情绪和他人情绪的认知、协调、引导、互动和控制,是建立和维护良好的情绪状态的一种现代管理方法。大学生情绪管理与压力应对策略包括问题关注策略、评价关注策略和情绪关注策略等。