Preschoolers' Reasoning about Density: Will It Float?

Density is a complex concept found to appear late in development. However, density has a readily apparent empirical consequence—buoyancy. Early scientific understanding of density arose through Archimedes' discovery of water displacement as a function of density, and young children have experience playing with objects in water. Therefore, a buoyancy prediction task was developed in order to access preschoolers' early understanding of density. 3–5-yearold children from 2 preschool classes, as well as adults, made buoyancy predictions for a set of objects that varied systematically in density, weight, and volume. 4–5-year-olds (from the older class) and adults were shown to demonstrate similar patterns in their judgments. Objects much more or much less dense than water were more accurately judged than objects with densities closer to the density of water. Weight and volume were found to "interfere" in these judgments in systematic ways for the older class of children and the adults. Children in the younger class (3-year-olds) showed a mean proportion correct performance of .53; they all passed a pretest, however, and no child refused to make judgments.     

Twelve-Month-Old Infants Respond to Speech About Absent Inaccessible Objects

This article investigated the interplay of 12-month-old infants’ perception of affordances for locomotion and their ability to respond to the mention of hidden objects. In Experiment I, a toy was hidden in an ottoman that was placed on a cabinet out of infants’ reach. Infants were more likely to look at, point to or approach the ottoman when there were stairs leading to it than when there were none. The stairs did not help infants respond by highlighting the target corner of the room (Experiment II) or by boosting their engagement with the study events (Experiment III). This suggests that infants’ perception of the accessibility of the hiding location influences their ability to respond to speech about absent things.     

Early reading success and its relationship to reading achievement and reading volume: replication of ‘10 years later’

Cunningham and Stanovich reported a longitudinal investigation over 10 years that examined the unique influence of exposure to print in explaining individual differences on various measures of reading achievement and declarative (general) knowledge. The present study replicated their investigation with a larger number of participants and additional measures of literacy and language skills. Fifty-four 1st graders were administered reading, spelling, vocabulary, IQ, and listening comprehension measures and then followed to the end of 10th grade. At the end of 10th grade, they were administered an IQ test and measures of reading comprehension, language ability, general knowledge, and exposure to print. Results showed that 1st grade reading skills were a strong predictor of 10th grade outcomes. Second and third-grade reading skills were predictive of individual differences in print exposure even after 10th grade reading comprehension and language ability had been partialed. Individual differences in print exposure also predicted differences in the growth of reading ability, word decoding, spelling, vocabulary, and listening comprehension throughout the elementary grades. Findings confirm the powerful, long-term benefits of providing children with a fast start in reading and support the reciprocal nature of strong reading skills and engagement in reading and reading-related activities.     

Potential of one-to-one technologies in the classroom: teachers and students weigh in

Increased efforts to promote 21st century learning emphasize the central role of technology in instructional delivery in order to advance the multifaceted abilities and skills required for student success in an increasingly technology-rich learning and work environment. A qualitative study was conducted in a large, economically diverse, mid-Atlantic school district to examine the implementation of six technology devices in 18 elementary, middle, and high school classrooms. The purpose was to understand teachers’ and students’ experiences related to the instructional implications of each device to inform long term, one-to-one implementation of an appropriate technology device to meet the district’s strategic goals for a 21st century learning environment. Teacher interviews and student focus groups revealed several themes related to technology integration, factors influencing implementation, impact on instruction, and impact on student motivation and engagement. Findings are discussed in relation to the district infrastructure and other considerations to support a one-to-one teaching and learning environment and how each of the six devices support the establishment of 21st century learning environments.     

Academic discipline and generalizability of student evaluations of instruction

Previous research on the generalizability of student ratings of instruction has raised questions about the effects of academic discipline and item types on the generalizability of these data for making relative decisions about instructors and about courses. In particular, although student evaluation data appear to provide a reasonable basis for making decisions about instructors when generalizing across courses and students, when course is the object of measurement, the data appear to be less generalizable. It was suggested in the literature that this may be due to the type of evaluation items used or it may be due to academic discipline differences in the type of courses selected for study. This study used Biglan's (1973a) model for classifying disciplines along the dimensions of paradigmatic/preparadigmatic (hard/soft) and pure/applied. A nested sampling procedure yielded two sample types: courses within teachers, in which individual instructors taught more than one course; and teachers within courses, in which individual courses were taught by more than one instructor. For each sample type, evaluation forms for twenty courses within each discipline classification were sought. The evaluation items for this study were classified as measuring six dimensions of instruction: organization, breadth of coverage, group interaction, enthusiasm, grading, and individual rapport. Generalizability and decision studies were conducted in which, for one sample, teacher was the object of measurement, and for the second sample, course was the object of measurement. Results indicated that reliable decisions about instructors could reasonably be made from all six of the evaluation dimensions; however, reliability for course decisions varied greatly with the evaluation dimension, being highest for breadth of coverage and lowest for grading. The same general pattern was noted for the paradigmatic disciplines and the preparadigmatic-applied disciplines but not for the preparadigmatic-pure disciplines. It is suggested that a single evaluation instrument may not be uniformly applicable to all discipline areas.     

The Next Big Idea: A Framework for Integrated Academic and Behavioral Intensive Intervention

Despite advances in evidence‐based core instruction and intervention, many students with disabilities continue to achieve poor academic and behavioral outcomes. Many of these students are not sufficiently responsive to standardized programs and require more intensive, individualized supports. While many interventions and school problem‐solving teams focus primarily on either academic or behavioral concerns, students with the most intensive needs often have interrelated needs in both areas. The next big idea in special education should be to merge these efforts, building upon all that we have learned about problem solving at all levels of support, to improve outcomes for these students. Data‐based individualization provides a framework for integrating academic and behavioral problem solving and intervention.     

Proponents of Creationism but not Proponents of Evolution Frame the Origins Debate in Terms of Proof

In Study 1, 72 internet documents containing creationism, ID (intelligent design), or evolution content were selected for analysis. All instances of proof cognates (the word “proof” and related terms such as “proven”, “disproof”, etc.) contained within these documents were identified and labeled in terms of the manner in which the terms were used. In Study 2, frequency counts for six terms (proof, evidence, establish, experiment, test, trial) were conducted on a sample of peer-reviewed research articles in the journal Science and the 72 internet documents included in Study 1. Quantitative and qualitative analyses revealed that proponents of creationism were much more likely than proponents of evolution to frame the creationism/evolution issue in terms of proof (ID proponents fell partway between the other two). Proponents of creationism frequently described empirical data favoring their position as proof of their position. Even more frequently, proponents of creationism described evolutionary scientists as being engaged in failed attempts to prove the truth of the evolutionary position. Evolution documents included fewer proof cognates than creationism or ID documents and the few proof cognates found in evolution documents were rarely used to describe the status of the theory of evolution. Qualitative data analysis indicated that proof cognates were often used to indicate certainty. The asymmetry between evolution and creationism documents was limited primarily to proof cognates; there were no major asymmetries for the terms evidence, establish, experiment, test, and trial. The results may reveal differences in the epistemological commitments of the involved parties.     

An alternative teaching method of conditional probabilities and Bayes' rule: an application of the truth table

This paper presents a comparison of three approaches to the teaching of probability to demonstrate how the truth table of elementary mathematical logic can be used to teach the calculations of conditional probabilities. Students are typically introduced to the topic of conditional probabilities—especially the ones that involve Bayes' rule—with the help of such traditional approaches as formula use or conversion to natural frequencies. The truth table approach is an alternative method for explaining the concept and calculation procedure of conditional probability and Bayes' rule.     

Undergraduate Research Methods: Does Size Matter? A Look at the Attitudes and Outcomes of Students in a Hybrid Class Format versus a Traditional Class Format

The goal of this study is to understand if there are any variations regarding student engagement and course outcomes based on the course format. A new course format was introduced in fall of 2006 that involves a hybrid approach (large lecture with small recitations) with a higher level of student enrollment than traditional research methods courses. During the same time frame, the discipline maintained its traditional research methods courses as well. A survey was administered to all students enrolled in research methods regardless of course format in fall 2006 and spring 2007. Student responses are discussed, including information concerning the preparation, design, cost and benefits of offering a hybrid research methods course format.