Age and directed-participation variables influencing the effectiveness of televised instruction in concrete operational behaviors

Head Start preschoolers on an isolated Papago reservation in southern Arizona were subjects of two studies of the effects of televised instruction and directed participation on teaching enumeration and conservation skills. Television instruction was most effective when used with active, directed participation and corrective feedback, but this, as well as amount and skills learned, varied with age. The televised segments used linear sequencing rather than the fragmented approach of Sesame Street. This research was supported in part by grant OCD-CB-479 from the Children’s Bureau, Office of Child Development, U.S. Office of Education. The authors appreciate the cooperation and participation of the Papago Tribe and the staffs of Head Start centers at San Xavier, Sells, and Pisinimo, Arizona. Special thanks are extended to Thora Schultz, who facilitated liaison on the Papago Reservation, and Margie Francisco, Elizabeth Siqueros, Edith Manuel, Pat Mendez, Elaine Williams, and Irma Dean Edmund, who contributed to instructional development and data collection.     

The relative responsiveness of concrete operational seventh grade and college students to science instruction

Numerous persons have suggested that instruction should match the developmental level of the learner. Are “concrete operational” college students developmentally the same as “concrete operational” seventh grade students thus in need of identical instruction? Matched concrete operational seventh grade and college students were given identical classroom instruction in probabilistic and correlational reasoning. The college students performed significantly better on posttest measures which appeared to require greater processing of information while significant differences did not exist on less difficult items. Level of cognitive development, field independence, and fluid intelligence correlated moderately with posttest performance for the seventh grade students. Field independence and fluid intelligence correlated moderately with posttest performance for the college students but not pretest knowledge of specific biological concepts and cognitive level. It was concluded that college students are more responsive to instruction due either to (1) greater amount of experience or (2) greater information processing capacity. Implications for science teaching are discussed.     

职业教育课程、教学范式的演变

随着经济的发展，以及认识论、学习理论等相关理论的演进，职业教育研究范式也经历了从社会效率主义到新职业主义的演变。但是，目前这些范式都遇到了困难，制约了知识经济时代职业教育课程、教学的进一步改革。为此，我们需要寻求新的范式。笔认为，当前在教育研究中比较流行的一种认识论－建构主义，可以为此提供很好的范式。     

Factors in the development of proportional reasoning strategies by concrete operational college students

This study was designed as a test for two neo-Piagetian theories. More specifically, this research examined the relationships between the development of proportional reasoning strategies and three cognitive variables from Pascual-Leone's and Case's neo-Piagetian theories. A priori hypotheses linked the number of problems students worked until they induced a proportional reasoning strategy to the variables of M-space, degree of field dependence, and short-term storage space. The subjects consisted of students enrolled in Physical Science I, a science course for nonscience majors at the University of Southern Mississippi. Of the 34 subjects in the study, 23 were classified as concrete operational on the basis of eight ratio tasks. Problems corresponding to five developmental levels of proportional reasoning (according to Piagetian and neo-Piagetian theory), were presented by a microcomputer to the 23 subjects who had been classified as concrete operational. After a maximum of 6 hours of treatment, 17 of the 23 subjects had induced ratio schemata at the upper formal level (IIIB), while the remaining subjects used lower formal level (IIIA) schemata. The data analyses showed that neither M-space and degree of field-dependence, either alone or in combination, nor short-term storage predicted the number of problems students need to do until they induce an appropriate problem-solving strategy. However, there were significant differences in the short-term storage space of those subjects who mastered ratio problems at the highest level and those who did not. Also, the subjects' degree of field-dependence was not a predictor of either the ability to transfer problem-solving strategies to a new setting or the reuse of inappropriate strategies. The results of this study also suggest that short-term storage space is a variable with high correlations to a number of aspects of learning such as transfer and choice of strategy after feedback.     

Differential response to structure of advance organizers in science instruction

In an experiment designed to investigate individual differences in learning from written materials preceded by advance organizers, 89 fourth-grade subjects were randomly assigned to treatment conditions in which programmed material on insects was preceded by one of three introductory passages containing: (1) higher level generalizations and specific examples; (2) higher level generalizations without examples; or (3) a control passage. Membership in treatment groups was determined by random assignment. Criterion performances were immediate and delayed posttest performance and errors during instruction. Analysis of variance results of treatment effects showed that the three treatments were about equally effective in terms of promoting retention and program errors. Simple regression analysis of Aptitude × Treatment interactions disclosed that Otis-Lennon IQ scores interacted significantly with instructional treatments for program errors showing a negative relationship between IQ scores and the degree of structure provided by the advance organizers.     

高职CAD/CAM教学亟待解决的问题

CAD(Computer Aided Design,计算机辅助设计)/CAM(Computer Aided Made,计算机辅助建造)是指结合专业技术、通过计算机系统辅助进行设计与建造的一门应用性很强的新兴学科。当前,在许多高等职业技术学校,虽然开展了CAD/CAM方面的教学,开出了一些相关课程;但是,由于对CAD/CAM究竟最应该学习什么和怎样学习等问题认识不足;所以,各个学校在CAD/CAM方面的教学内容、教学方法和教学水平等方面参差不齐,远远不能适应社会经济发展和企业技术进步对高等职业教育在CAD/CAM教学方面提出的要求。因此,有必要就以下几个问题认真讨论一下,以统一认识,明确方向。     

Scaffold instruction at the workplace from a situated perspective

This article proposes the need to address scaffold instructions from a situated learning perspective. Based on an empirical study of how apprentice bakers learn their trade, it is claimed that studies of learning at the workplace yield important insights into our understanding of scaffold instructions. Seen from the perspective of the apprentices, scaffold instruction represents access to more responsibility in practice, it supports their identities as future bakers and they learn bodily know-how. When scaffold instruction failed, it was often in relation to situations where the apprentices were placed in marginal positions in the community of practice or in relation to a central workplace situation.     

Teaching the partial products algorithm with the concrete representational abstract sequence and the strategic instruction model

Elementary standards include multiplication of single-digit numbers and students advance to solve complex problems and demonstrate procedural fluency in algorithms. The ability to illustrate procedural fluency in algorithms is dependent on the development of understanding and reasoning in multiplication. Development of multiplicative reasoning provides the foundation for advanced mathematics and algebraic reasoning. For students who struggle in mathematics, instruction in multiplication algorithms should ensure conceptual understanding so that students have a foundation for success in advanced mathematics. The concrete representational abstract (CRA) sequence addresses conceptual understanding and the strategic instruction model (SIM) supports procedural knowledge. The current pilot study combined these methods to teach elementary students the partial products algorithm. Twelve students in grades four and five participated in the study, receiving instruction from teachers in their school during an intervention period. Within a pre-experimental design, using pre- and postintervention data, students showed a significant change in performance. The article will describe and show how teachers implemented the CRA-SIM interventions and discuss implications for practice.     

初中化学分层教学的探索与实践

在传统的班级授课制的教学模式下运用分层教学的教学策略,可以使教学活动更有效地面向全体学生,促进不同层次的学生在原有基础上获得发展。     

利用高延性水泥基材料抑制钢/混凝土连接区域的断裂破坏(英文)

为了避免混凝土的脆性断裂破坏,在钢/混凝土连接区域中用高延性水泥基材料(ECC)代替了普通混凝土. 采用剪力键/ECC 的抗剪试验、二维锚固螺栓/ECC 拔出试验和有限元模拟研究了 ECC 材料的延性对于连接区域破坏模式、结构性能的影响. 实验结果表明: 通过微观力学原理设计的 ECC 具有 300 倍于普通混凝土的拉伸延性,从而使钢/混凝土连接区中混凝土断裂破坏模式由脆性转变为延性. 混凝土材料的高延性使结构承载能力和变形性能获得改善,这也同时为有限元模拟结果所验证. 通过改变混凝土材料延性而提高结构性能的理念也可在其他类似的钢/混凝土组合结构中得到应用.