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241.
The learning cycle is a method of teaching—it is also a curriculum organization principle and is derived directly from the mental functioning model invented by Piaget. Although Jean Piaget contributed to the formation of the learning cycle (Piaget, 1973), its present structure has to be attributed to Dr. Robert Karplus and the persons who developed the materials of the Science Curriculum Improvement Study (SCIS). It was through the SCIS activities that many of us learned how to develop curricula and teach with the learning cycle. The learning cycle is built upon the premise that three distinct phases are necessary in developing understanding of a concept, that those phases have a definite sequence, and each phase has a definite structure or form. The research done in testing the form variable has already been reported in this journal (Renner, Abraham, & Birnie, 1985). This report explores whether or not each learning-cycle phase is necessary in learning a concept. 相似文献
242.
The goal of this study was to examine the means used by textbook authors to introduce, define, and explain the mole concept in high school and introductory college chemistry textbooks. The analysis was framed by four questions:
- 1 How is the mole defined?
- 2 What concepts about the atom are introduced prior to the mole?
- 3 Is Avogadro's constant presented as an experimentally determined value?
- 4 What is the context for introducing the mole?
- 1 Two ways of defining the mole dominate the texts. One way defines the mole as Avogadro's number (6.02 × 1023) particles; the other method defines the mole in terms of carbon-12.
- 2 All texts that present a definition in terms of C-12 introduce and define concepts about the atom prior to introducing the mole.
- 3 Most texts at all levels point out that the value 6.02 × 1023 is an experimentally determined quantity.
- 4 Nearly all texts discuss the mole in relation to die problem of finding a way to count particles that are too small to be directly weighed. Most texts also use a familiar counting unit, such as the dozen, to introduce the mole by analogy.
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In Grutter vs. Bollinger, the U.S. Supreme Court ruled that the use of race as one factor, among many in admissions decisions is constitutional. It is not known, however, whether future legal opinions will continue to uphold the use of affirmative action policies. Some have argued that class-based preferences can achieve many of the same goals as in affirmative action while being more likely to withstand legal challenges. To date, no empirical studies have been conducted on the potential impact of a class-based admissions policy if implemented at an undergraduate institution. This paper reports on a study at a selective public college and compares a number of outcomes under three admissions models: the original admissions decisions, a purely academic model, and an socio-economic status (SES)-based model. The findings showed that use of the SES-based model would have led to a more academically qualified class than in the original admitted class while maintaining substantially greater student diversity that was found under the academic model. An admissions policy based on preferences for socio-economically disadvantaged applicants appears to hold promise for other colleges and universities with similar institutional and applicant characteristics. The ideas and research design reported in this paper are based on the doctoral dissertation study of the second author, Undergraduate Admissions Models Incorporating Socioeconomic Factors (Johnson, 2000). 相似文献
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This article attempts to characterize the general problem of selecting methods for decision-making. The traditional rational approach to choice is from economics, which offers expected-value maximization. The task environment of decision method selection, however, does not seem to provide the data necessary for carrying out the expected-value calculations. Our approach uses methods from the field of cognitive science. We develop the notion of domain size in fields such as chess, borrowing the concept of a chunk from human memory. We then develop a heuristic rule for choiceamongmethods. We propose this rule as one of many possible rules. 相似文献
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John M. Reveles Gregory J. Kelly Richard P. Durán 《Cultural Studies of Science Education》2007,1(3):467-495
This ethnographic study of a third grade classroom examined elementary school science learning as a sociocultural accomplishment.
The research focused on how a teacher helped his students acquire psychological tools for learning to think and engage in
scientific practices as locally defined. Analyses of classroom discourse examined both how the teacher used mediational strategies
to frame disciplinary knowledge in science as well as how students internalized and appropriated ways of knowing in science.
The study documented and analyzed how students came to appropriate scientific knowledge as their own in an ongoing manner
tied to their identities as student scientists. Implications for sociocultural theory in science education research are discussed.
John Reveles is an assistant professor in the Elementary Education Department at California State University, Northridge. He received
his Ph.D. from the University of California, Santa Barbara in 2005. Before pursuing his Ph.D., he worked as a bilingual elementary
school teacher for 3 years. His research focuses on the development of scientific literacy in elementary school settings;
sociocultural influences on students' academic identity; equity of access issues in science education; qualitative and quantitative
research methods. Within the Michael D. Eisner College of Education, he teaches elementary science curriculum methods courses,
graduate science education seminars, and graduate research courses.
Gregory Kelly is a professor of science education at Penn State University. He is a former Peace Corps Volunteer and physics teacher. He
received his Ph.D. from Cornell in 1994. His research focuses on classroom discourse, epistemology, and science learning.
This work has been supported by grants from Spencer Foundation, National Science Foundation, and the National Academy of Education.
He teaches courses concerning the uses of history, philosophy, sociology of science in science teaching and teaching and learning
science in secondary schools. He is editor of the journal Science Education.
Richard Durán is a Professor in the Gevirtz Graduate School of Education, University of California, Santa Barbara. His research and publications
have been in the areas of literacy and assessment of English Language Learners and Latino students. He has also conducted
research on after school computer clubs, technology and learning as part of the international UC Links Network. With support
from the Kellogg Foundation, he is implementing and investigating community and family-centered intervention programs serving
the educational progress of Latino students in the middle and high school grades. 相似文献