Three concepts or one? Students’ understanding of basic limit concepts

In many mathematics curricula, the notion of limit is introduced three times: the limit of a sequence, the limit of a function at a point and the limit of a function at infinity. Despite the use of very similar symbols, few connections between these notions are made explicitly and few papers in the large literature on student understanding of limit connect them. This paper examines the nature of connections made by students exposed to this fragmented curriculum. The study adopted a phenomenographic approach and used card sorting and comparison tasks to expose students to symbols representing these different types of limit. The findings suggest that, while some students treat limit cases as separate, some can draw connections, but often do so in ways which are at odds with the formal mathematics. In particular, while there are occasional, implicit uses of neighbourhood notions, no student in the study appeared to possess a unifying organisational framework for all three basic uses of limit.     

Yo-Yo Intermittent Endurance Test-Level 1 to monitor changes in aerobic fitness in pre-pubertal boys

The present study aimed to examine the performance and heart rate responses during the Yo-Yo Intermittent Endurance Test-Level 1 (Yo-Yo IE1) in children under the age of 10. One hundred and seven male children (7–9 years) performed the Yo-Yo IE1 at the beginning (M₁), middle (M₂) and end (M₃) of the school year. Data from individual heart rate curves of the Yo-Yo IE1 were analysed in order to detect the inflection point between an initial phase of fast rise in heart rate values and a second phase in which the rise of the heart rate values is much smaller. The distance covered in the Yo-Yo IE1 improved from M₁ to M₃ (884 ± 496 vs. 1032 ± 596 m; p < 0.05; d = 0.27), with intermediate values for M₂ (962 ± 528 m). Peak heart rate (HR_peak) decreased from M₁ to M₂ and M₃ (204 ± 9, 202 ± 9 and 200 ± 9 bpm, respectively; p < 0.05; d = 0.25–0.42). The 7th shuttle of the test (280 m), corresponding to 2.5 min, was identified as the inflection point between the two phases. Also, absolute heart rate at the 7th shuttle decreased progressively throughout the year (185 ± 9, 183 ± 10, and 179 ± 10 bpm; p < 0.05; d = 0.31–0.61). The present study provides evidence of the usefulness of a maximal as well as a submaximal version of Yo-Yo IE1 as a tool to monitor changes in aerobic fitness in pre-pubertal children.     

Relationship between physical activity,physical fitness and multiple metabolic risk in youths from Muzambinho's study

Negative associations between physical activity (PA), physical fitness and multiple metabolic risk factors (MMRF) in youths from populations with low PA are reported. The persistence of this association in moderately-to highly active populations is not, however, well established. The aim of the present study was to investigate this association in a Brazilian city with high frequency of active youths. We assessed 122 subjects (9.9?±?1.3 years) from Muzambinho city. Body mass index, waist circumference, glycaemia, cholesterolaemia, systolic and diastolic blood pressures were measured. Maximal handgrip strength and one-mile walk/run test were used. Leisure time PA was assessed by interview. Poisson regression was used in the analysis. The model explained 11% of the total variance. Only relative muscular strength and one-mile walk/run were statistically significant (p?相似文献   

Analysis of the intraseasonal stability of field test performances in young academy soccer players

This study aimed to observe the intraseasonal stability of anthropometric, technical and functional test results in academy soccer players of different age categories. In total, 103 participants (age range: 7.7–13.4 years) by 5 age categories of the same academy were recruited for this study. Players were submitted to a field-test battery comprising 3 anthropometric measurements (body mass, stature and body mass index), 6 soccer technical tests (to assess the ability of ball control, ball control with the head, pass accuracy, shooting accuracy, dribbling and dribbling with pass) and 3 functional tests (countermovement jump with the hands on the hip, countermovement jump with free hands and 15-m linear sprint) that was administered in 4 test sessions during the same season. Though anthropometric results showed a clear increment in each age category across the season, the fluctuation of technical test results depended on age category and test session. Moreover, a significant increase in the results of functional tests was observed in most of the age categories, in particular, for the assessment of lower power limb. In conclusion, collecting repeated intraseason measurements permits the identification of players’ fluctuations of performance across the season and allows coaches to make frequent adjustments of their programmes.     

Proposing Questions for Scientific Inquiry and the Selection of Science Content in Initial Elementary Education Teacher Training

Research in Science Education - This article presents a qualitative study of the type and quality of questions formulated by prospective elementary teachers (PETs) when designing scientific inquiry...     

Investigating Image Formation with a Camera Obscura: a Study in Initial Primary Science Teacher Education

Research in Science Education - This article presents the results of a qualitative study aimed at determining the effectiveness of the camera obscura as a didactic tool to understand image...     

A probabilistic approach to student workload: empirical distributions and ECTS

The ECTS, European Credit Transfer System, is now widely used throughout higher education institutions as it facilitates student mobility within Europe and the comparison of study programs and courses. Most European institutions provide students with the number of ECTS each course and module is worth. A full-time student needs to complete 60 ECTS per academic year, which represents about 1500 to 1800 h of study. However, there is a lack of research showing that ECTS metrics have been properly implemented in different degrees and universities. The aim of this paper is to assess the relevance of the ECTS metric as a valid indicator of students’ and courses’ workloads. Detailed workload measurements have been taken in two Spanish universities, with 250,000 work hours monitored from 1400 students. This is the first study published with such a large dataset that includes a range of simultaneous courses and throughout a whole semester. Empirical distribution functions of workload indicators have been obtained. Evidence is provided indicating that nominal ECTS credit hours may be overestimated, that the variability of student workload could be too large for ECTS to sensibly characterize course workload, and that workload statistics of courses with same nominal ECTS are generally not comparable. Although the ECTS metric conception seems to be a valid metric to facilitate mobility between different institutions and higher education systems, in practice, according to this study, it requires revision, at least in the two institutions that have been included in this study. Further studies like the present one are required to test if this is a broader problem that has implications for the comparability of degrees across Europe.     

Islamic religious education and the plan against violent radicalization in Spain

ABSTRACT

This article analyses the importance of Islamic religious education in public schools in Spain as an instrument in the prevention and fight against violent radicalisation. In this article, we examine the legal status of Islamic religious education and the latest regulations on Islamic religious education that emphasise the fight against Islamist terrorism. We also study the regulation of teachers of Islamic religious education and their role in the counter-narrative required to deter the message of Islamist terrorists and prevent violent radicalisation.     

Elementary students’ metacognitive processes and post-performance calibration on mathematical problem-solving tasks

Calibration, or the correspondence between perceived performance and actual performance, is linked to students’ metacognitive and self-regulatory skills. Making students more aware of the quality of their performance is important in elementary school settings, and more so when math problems are involved. However, many students seem to be poorly calibrated, with a tendency towards over-confidence. The present study analyzes the relationship between post-performance calibration accuracy and the metacognitive process shown by 524 fifth- and sixth-grade students while solving two math problems. After calculating a calibration index and establishing the stability of students’ judgments and actual performance, differences in the metacognitive process exhibited by students with different calibration accuracy (Accurate vs. Inaccurate groups) were analyzed. The emergence of different calibration patterns and differences in the metacognitive process as a function of mathematics achievement and grade level were also examined. Results indicated that: (a) students in the overall sample were little calibrated and over-confident, showing high stability in their judgments and actual performance across problems; (b) inaccurate students reported using information representation sub-processes (drawing/summarizing) less frequently, but writing and reviewing (and also correcting mistakes) more frequently than their accurate peers; and (c) differences in calibration patterns and the metacognitive process were found when achievement level was considered, whereas grade level did not generate any important effect. These findings suggest the usefulness of process-based measures to examine the metacognitive processes involved in making post-performance judgments, considering achievement and its possible mediating role in this relationship.     

Cognitive,Motivational, and Volitional Dimensions of Learning: An Empirical Test of a Hypothetical Model

The principal aim of this research is to contrast empirically a hypothetical model developed on the basis of the fundamental assumptions of current self-regulated learning models. In line with evaluation criteria of model fit, a high rate of congruence between the hypothesized theoretical model and the empirical data was observed. Analysis of the effects between the variables of the model revealed the following relevant aspects: students' predisposition to feel responsible for the results of their academic behavior (internal attribution) is related to positive self-image (academic self-concept), both being important conditions for development of learning-oriented motivation (learning goals). All of this involves selection and use of learning strategies for deep information processing (deep learning strategies), which leads students to assume responsibility with high levels of persistence, perseverance, and tenacity so as to achieve goals defined by the motivational orientation. This persistence and effort to achieve the proposed goals has in turn a positive and significant effect on academic achievement.