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Opium poppy (Papaver somniferum) is one of the world’s oldest medicinal plants and a versatile model system to study secondary metabolism. However, our knowledge of its genetic diversity is limited, restricting utilization of the available germplasm for research and crop improvement. We used genotyping-by-sequencing to investigate the extent of genetic diversity and population structure in a collection of poppy germplasm consisting of 91 accessions originating in 30 countries of Europe, North Africa, America, and Asia. We identified five genetically distinct subpopulations using discriminate analysis of principal components and STRUCTURE analysis. Most accessions obtained from the same country were grouped together within subpopulations, likely a consequence of the restriction on movement of poppy germplasm. Alkaloid profiles of accessions were highly diverse, with morphine being dominant. Phylogenetic analysis identified genetic groups that were largely consistent with the subpopulations detected and that could be differentiated broadly based on traits such as number of branches and seed weight. These accessions and the associated genotypic data are valuable resources for further genetic diversity analysis, which could include definition of poppy core sets to facilitate genebank management and use of the diversity for genetic improvement of this valuable crop.

Theories are used in instructional design to produce instruction that is effective and efficient. Learners, however, may not be drawn into instruction because it lacks relevance and appeal. Motivational design theory is used in concert with instructional theory to produce instruction that is both appealing and effective.

This paper is intended to begin codifying guidelines of user interface design for computer-based learning environments. Data was collected from an analysis of the literature, an analysis of commercial computer-based learning environments, and interviews with the designers and developers of the analyzed programs. The guidelines presented in this paper are not hard andfast rules of what to do and when to do it, but rather represent a collection of issues to consider when designing and developing the visual user interface.

Performance assessment in science focuses on measuring achievement of problem solving, higher-order thinking, and application of skills and knowledge. Descriptions of how performance assessment tasks are linked to science curriculum objectives are given, along with criteria for and examples of performance assessment tasks. Criteria for developing scoring procedures are considered. Throughout the discussion, the role that computers and related technology can play in problem-based performance assessment is described.

The effects of a mastery learning strategy modified to limit diagnosis to two cycles were tested with high school chemistry students. The results indicate that achievement of mastery learning students was significantly greater than that of nonmastery control students. On-task behavior (academic engagement) of mastery learning students increased in a linear fashion during the study (45 instructional days), while on-task behavior of nonmastery students decreased. Attitudes toward science and science instruction were not significantly different but were positive in both mastery and nonmastery conditions.

This study is a meta-analysis of the question “What are the effects on achievement of different teaching techniques?” Twelve categories of teaching techniques were specified. Among these are questioning, wait-time, testing, focusing, manipulative, presentation approach, inquiry or discovery, audio-visual, and teacher direction. A coding form was then developed to allow for the uniform examination and recording of 76 variables from each study. One or more effect sizes were calculated and coded for each study. Over 300 microfilmed dissertations covering the past 30 years were examined. Some 2000 ERIC science abstracts were reviewed and suitable studies obtained. Finally, journal articles were reviewed. A total of 400 effect sizes representing 160 studies were produced. The main effect size overall was 0.34. Thus, for all samples considered the experimental science teaching techniques on the average resulted in one-third of a standard deviation improvement over traditional techniques. Mean effect sizes also were calculated for each technique. More than 20 other variables such as class size, community type, and science subject area were cross-tabulated with effect size.

EDRS'PRICE MF-$0.76 HC-$1.58 PLUS POSTAGE bESCRIPTO?S *Academic Achievement; Academic Aptitude; Achievement Rating; Diagnostic Tests; Educational Strategies; Elementary Education; *Elementa\ry School Students; Geometry; Individual Differences; Individualized Instruction; *Instructional Innovation; Learning Motivation; *Remedial Instruction; Statistical Analysis; *Student Evaluation; Teaching Methods IDENTIFIERS *Mastery Learning

The purpose of this study was to measure the effects of three variations in the use of diagnostic-prescriptive teaching on the cognitive and affective biology achievement of high school students. These variations included (a) no diagnostic-prescriptive assistance, a control group, (b) teacher-managed diagnosis and prescription, and (c) student-managed diagnosis and prescription. Specific questions addressed in this study included: 1.What are the effects of differing types of diagnostic-prescriptive learning assistance on the biology achievement of students? 2.What are the effects of aptitude on the biology achievement of students? 3.What are the effects of locus of control perception on the biology achievement of students? 4.What are the effects of differing types of diagnostic-prescriptive learning assistance on the attitudes of high school biology students toward subject matter and instruction?

The purpose of this study is to examine integrated process skill and formal thinking abilities of middle and high school students and determine the relationship, if any, between the two. A relationship was thought to exist since both sets of skills strongly emphasize conducting fair experiments as well as other abilities. Pencil and paper measures of formal operational and integrated process skill achievement were given to almost 500 grade 7–12 students. Resulting correlations showed a strong relationship between achievement on the two meansures (r = 0.73) and all subtests of both measures. Factor analysis data corroborate the correlational evidence. One potential inference to be drawn from these results is that process skill teaching might influence formal thinking ability. A follow-up experimental study will determine this.

While the philosophical importance of the integrated science process skills is often unchallenged, there is a lack of research with middle and secondary school students to indicate when or how these skills might best be taught. In this study different patterns and amounts of instruction on planning experiments were used with sixth- and eighth-grade students. A model for generating integrated process skill lessons was used to produce all lessons. Treatment One involved a two-week introductory unit on integrated process skills, followed by one period-long process skill activity per week for 14 weeks. Treatment Two involved only the same two-week introductory unit. Treatment Three was a contrast group which received only content oriented instruction. Results showed that both sixth- and eighth-grade students can learn to use certain integrated process skills; growth was apparent in identifying variables and stating hypotheses. Differences generally favored treatment one over treatment three. No differences favoring any treatment were found for formal operational ability outcomes.

Two great goals of science instruction are dis cussed here: teaching students to learn on their own and teaching students to acquire and proc ess information, rather than merely memorizing facts. The author mentions several programs that facilitate attaining these goals.

EVALUATION QUESTIONS This paper describes methods of assessing the impact on students of a teacher's use of skills learned in a training program. Although we describe a particular set of training materials and methods for measuring their effectiveness, the intention is to illustrate evaluation designs that have wide application for assessing the effects of using teaching skills in terms of student outcomes.

The purpose of this study was to test Gagne’s hypothesis that attention to prerequisites should be more effective than repeated practice of a final task when learning intellectual skills. Ninety eighth-grade general science students studied self-instructional materials on the construction and interpretation of graphs. After each of three lessons each subject took a diagnostic test covering the objectives of the instruction. Subjects in Group 1 received additional instruction on prerequisites as remediation. Subjects in Group 2 received additional practice items as remediation, and subjects in Group 3 received no remedial activity. Students receiving remedial instruction did significantly better than those receiving only main-line instruction. Students receiving additional instruction on prerequisites did significantly better than those receiving additional practice items as remediation.

SOME DEFINITIONS The idea that learning is cumulative or hierarchical is a commonsense notion. Intuitively one feels that a learner must master arithmetic before tackling algebra or must learn to distinguish certain letter sounds before learning to read. As a result, certain school courses may be listed as prerequisites for other courses. A group of topics may be ordered in sequence within courses under the assumption that one topic should be studied before another. Efforts have been made also at sequencing instruction on a level more detailed than courses or topics within a course. The aim has been to develop sequences of learning tasks at a level of single performance outcomes.