The nature and development of preservice science teachers' conceptions of subject matter and pedagogy

The purpose of this study was to assess the development and changes in preservice science teachers' subject matter and pedagogy knowledge structures as they proceeded through a professional teacher education program. Twelve secondary preservice science teachers were asked to create representations of their subject matter and pedagogy knowledge structures periodically (four times spanning the entirety of their subject-specific teacher education program) and participate in a videotaped interview concerning the eight knowledge structure representations immediately following student teaching. Qualitative analyses of knowledge structure representations and transcribed interviews within and between subjects were performed by one of the researchers and “blindly” corroborated by the other two researchers. Initial knowledge structure representations were typically linear and lacked coherence. Both types of knowledge structure representations were highly susceptible to change as a consequence of the act of teaching. Although there was some overlap between subject matter and pedagogy knowledge structures, they were reported to exert separate influences on classroom practice, with the pedagogy knowledge structure having primary influence on instructional decisions. Furthermore, the complexity of one's subject matter structure appeared to be a critical factor in determining whether the structure directly influences classroom practice.     

Contextual influences on the interaction between conflicting memories in the rat

Contextual events redundant to the learning, in sequence, of passive and active avoidance were of one type for the former task and of another for the latter. During later testing, these contextual events were found to determine which of these acquired, conflicting dispositions would be manifested in behavior. Mutual interference in retention otherwise seen under similar circumstances seemed subordinate to the influence of the three types of contextual stimuli tested—drug (pentobarbital), compound (the experimental room in which conditioning took place), and a relatively unitary stimulus (a constantly sounding buzzer). The discussion considered the defining characteristics of a “contextual stimulus” and the mechanisms through which contextual events control the manifestation of learned behaviors and alleviation of interference in retention.     

Social Influences on False Belief Access: Specific Sibling Influences or General Apprenticeship?

Some recent studies have found a relation between the number of siblings 3–4-year-old children have and their performance on false belief tasks. 2 experiments reported here examine a variety of factors in children's social environments, including daily contact with peers and adults as well as the numbers of their siblings, on a battery of false belief tests. In Experiment 1, 82 preschoolers were studied in Rethymnon, Crete, in order to obtain a range of extended kin available as a resource for the child. In Experiment 2, 75 Cypriot preschoolers were studied in Nicosia in order to examine the influences of each child's daily social contacts, as measured by maternal questionnaire. Logistic regression revealed that the factors which account for most of the predicted variance on the theory of mind tests were ( a ) the number of adult kin available (Experiment 1) or adults interacted with daily (Experiment 2), ( b ) the child's age, ( c ) the number of older siblings a child has, and ( d ) the number of older children interacted with daily. The results suggested that theory of mind is not simply passed from one sibling to another in a process of social influence. It seems more likely that a variety of knowledgeable members of her or his culture influence the apprentice theoretician of mind.     

Preparing student teachers for alternative assessment in science

This material is based upon work supported in part by a grant from the National Science Foundation California State University Student Teaching Development Project (DOE-9250027) and the W. M. Keck Foundation. Any opinions, findings, and conclusions or recommendations expressed in this article are those of the authors and do not necessarily reflect the views of the funding ordanizations.     

Leadership situations in academic departments: Relations among measures of situational favorableness and control

Measures of attributes of leadership situations faced by chairmen in academic divisions and departments were theoretically and empirically related. Measures of task structure and member relations were derived from Fiedler's (1967) Contingency Model of Leadership, and measures of total control and relative control were derived from Tannenbaum's (1967) Control Graph Theory. Two correlational studies using samples of community college divisions and university departments indicated that hypotheses derived from research undertaken in business and military settings were not generally supported in higher educational settings. Consistent findings across both studies indicated that high task structure (faculty homogeneity and academic task structure) is associated with better member relations and greater cooperation on administrative matters. Implications for administrators are briefly discussed.     

Changes in the retrievability of associations to elements of the compound CS determine the expression of overshadowing

In two experiments, rats were presented with a taste conditioned stimulus (CS) alone, an odor CS alone, or an odor-taste compound followed by lithium chloride injection. When tested 1 day following conditioning, there was evidence that the odor cue overshadowed conditioning to the taste; however, there was no indication of overshadowing following a longer (21-day) retention interval, despite undiminished strength of the aversion in animals conditioned with only the single element (taste). The overshadowing observed at the 1-day retention interval was not reciprocal. Rats conditioned with the odor CS alone or with the compound CS expressed odor aversions of comparable strength—that is, no overshadowing. However, in contrast to the taste aversion, overshadowing of conditioning to the odor by taste was evident following a 21-day retention interval. Rather than reflecting a failure of the overshadowed stimulus to acquire associative strength, these data suggest that overshadowing may be expressed, or not expressed, as a result of changes in the relative retrievability of learned associations over time.