Alternative Tasks for the Teaching and the Learning of functions: analysis of an intervention in the High School

In this paper we focus on the application of two mathematical alternative tasks to the teaching and learning of functions with high school students. The tasks were elaborated according to the following methodological approach: (i) Problem Solving and/or mathematics investigation and (ii) a pedagogical proposal, which defends that mathematical knowledge is developed by means of a balance between logic and intuition. We employed a qualitative research approach (characterized as a case study) aimed at analyzing the didactic pedagogical potential of this type of methodology in high school. We found that tasks such as those presented and discussed in this paper provide a more significant learning for the students, allowing a better conceptual understanding, becoming still more powerful when one considers the social-cultural context of the students.

Evaluation of the prevalence and nutritional and social determinants of overweight in a population of schoolchildren: a cross-sectional analysis of 5,037 children

Objective: To evaluate the prevalence and nutritional and social determinants of overweight in a population of schoolchildren in Southern Brazil. Methods: Cross-sectional descriptive study of 5,037 children of both genders, between 6 and 10.9 years of age, from public and private schools of Maringa, Parana, Brazil. Evaluation of factors associated with excess weight (overweight and obesity) included gender, age, school type, socioeconomic level, education of the head of the family, eating habits, and means of commuting to school. After univariate analysis (Fisher's exact test), we adjusted a logistic regression model and used Wald's test for decision-making (p < 0.05). Results: The mean age was 8.7 +/- 1.3 years, with 52.8% females; 79.1% of the students attended public school and 54.6% had families of socioeconomic class A or B. Regarding nutritional status, 24% of children were overweight (7% obesity, 17% overweight). Being male, attending a private school, and having a head of the family with over four years of education were significantly associated with excess weight. In relation to food, inadequate intake of,carbohydrates was associated with a 48% greater chance of overweight/obesity (p < 0.001; OR: 1.48; 95% CI: 1.25-1.76), Conclusion: The prevalence of overweight found in this study is approximate to that reported in national studies. Its association with gender and inadequate food intake indicates that these factors should be considered in initiatives aimed at preventive measures in childhood.

Influence of children's oral health-related quality of life on school performance and school absenteeism

Objective: This study assessed the relation of child oral health-related quality of life with school performance and school absenteeism. Methods: We followed a cross-sectional design with a multistage random sample of 312 12-year-old schoolchildren living in Brazil. The participants completed the child perceptions questionnaire (CPQ1114) that provides information about psychological factors, while their parents or guardians answered questions on their socioeconomic status measured by parents' education level and household income. A dental examination of each child provided information on the prevalence of caries and dental trauma. Data on school performance, which included the results of baseline Brazilian language (Portuguese) tests, and school absenteeism (school days missed) were obtained from the school register. Multilevel linear regression was used to investigate the association among psychological and socioeconomic status and children's school performance. Results: In the multiple model, after adjusting for individual covariates, being a girl was associated with higher school performance (P < 0.05), whereas low household income (P < 0.05), higher mean of CPQ1114 (P < 0.05), and higher school days missed (P < 0.001) were identified as individual determinants of lower school performance. When the school-level covariates were included in the model, the association between subjects' level characteristics and school performance still persisted. Conclusion: Children's school performance and absence were influenced by psychological and socioeconomic conditions.