Gender,text, and discussion: Examining intellectual safety in the science classroom

It is clear from the extant literature that gender inequities exist in a myriad of ways in science classrooms. Past research, however, has been conducted solely from researchers' observations and has neglected to investigate students' awareness of and reactions to their own experiences. Hence, this study focused on students' perceptions of gender differences in instructional activity and talk about that activity in physics and honors physics classes. Data analysis showed that although teachers may be unaware of gender inequities, students of both sexes are not unaware of such inequities. Females explained their fears of offering their opinions and participating in activities like labs and small-group or whole-class discussions. Differential language patterns were found for males and females, particularly when discussion was structured and rewarded for refutation. Explanations are offered for these disparities and suggestions are given for addressing gender bias in science classrooms. It has been well documented that science classrooms are not gender fair (Bazler & Simonis, 1991; Bianchini, 1993; Tobin, 1988). Teachers, texts, and the forms of instruction they perpetuate contribute to gender inequities in science instruction. For example, research tracing changes in science textbooks over time has shown that current texts have failed to eliminate barriers to women in science (Bianchini, 1993). Science textbooks are criticized for their unequal treatment of genders, with illustrations, photos, and texts of males far outnumbering those of females, despite the approximate 50/50 male/female ratio of our population (Bazler & Simonis, 1991). In addition to the proclivity of science textbooks to favor males, researchers speculate that the tendency for boys to achieve higher than girls in science may be a result of more opportunity to engage in academic tasks (Tobin & Garnett, 1987). Their behavior shows that teachers have differential expectations for students' responses in activities like teacher-led discussion. In teacher-led, whole-class discussion, boys are spoken to more frequently and are asked more higher-order questions (Becker, 1991; Hall & Sadler, 1982). Teachers in science classrooms elaborate more on males' responses than females' responses in large-group discussion of scientific concepts (Jones & Wheatley, 1990). © 1996 John Wiley & Sons, Inc.     

Coronavirus disease(COVID-19):The need to maintain regular physical activity while taking precautions

The on-going Coronavirus disease(COVID-19)outbreak in China has become the world's leading health headline and is causing major panic and public concerns.On January 30,2020,the World Health Organization(WHO)declared that the new coronavirus outbreak is a public health emergency of international concern.1 The virus has already had a direct impact on more than 10 million people in the city of Wuhan and has reached other parts of China as well,posing a health threat of unknown magnitude globally.As of February 8,2020,WHO reported 34,886 confirmed cases of COVID-19 globally,with 34,589 of them occurring in China(including 6101 severe cases and 723 deaths).A total of 288 other confirmed cases(with 1 death)have been reported in 24 countries,including Japan,Australia,Germany,and United States.2 However,these daily estimates are expected to rise even higher as reports from health authorities in China3 are gathered and near real-time updates of the Johns Hopkins virus dashboard are made 4 The outbreak has caused governments in various countries to take swift and protective measures.In China,these included putting cities on lockdown,5 implementing travel wamings/bans and cancellations,6 extending national holidays,and closing schools and postponing classes7.     

DNA microarray wet lab simulation brings genomics into the high school curriculum

We have developed a wet lab DNA microarray simulation as part of a complete DNA microarray module for high school students. The wet lab simulation has been field tested with high school students in Illinois and Maryland as well as in workshops with high school teachers from across the nation. Instead of using DNA, our simulation is based on pH indicators, which offer many ideal teaching characteristics. The simulation requires no specialized equipment, is very inexpensive, is very reliable, and takes very little preparation time. Student and teacher assessment data indicate the simulation is popular with both groups, and students show significant learning gains. We include many resources with this publication, including all prelab introductory materials (e.g., a paper microarray activity), the student handouts, teachers notes, and pre- and postassessment tools. We did not test the simulation on other student populations, but based on teacher feedback, the simulation also may fit well in community college and in introductory and nonmajors' college biology curricula.     

Desalination of masonry structures: Fine tuning of pore size distribution of poultices to substrate properties

Desalination is a relatively new intervention in the field of conservation of architectural heritage. Especially the desalination of immovable objects, such as masonry structures, is still a trial-error practice. In the field, different desalination materials and methods are used, sometimes with unsatisfactory results. Better understanding of the desalination process is needed in order to support the conservator with clear guidelines for choosing a suitable desalination material and method. The research presented in this paper constitutes the first step towards the development of a modular system of poultices, which can be adapted, i.e. fine-tuned to different types of substrates. Starting point is to make use of advection, i.e. the transport of salt ions with water flow. This transport mechanism is faster than diffusion and the application on immovable objects is relatively easy. In order to optimize salt extraction, a poultice working by advection should have smaller pores than the substrate. Starting from this principle the pore sizes of different desalination materials (sand, cellulose, kaolin and bentonite) mixed in different proportions, have been measured. Interesting results were obtained, showing that the desalination materials commonly used in the field are often not the most suitable ones. On the basis of the results, recipes for poultices, adapted to a specific substrate, can be formulated.     

“She My Friend”: Implications of Friend Ideologies,Identities, and Relationships for Bilingual Kindergarteners

This study identifies how the contextual features of an elementary school setting shaped and often restricted bilingual kindergarten students' access to friendships within their grade-level English-dominant classroom. Data demonstrate how students utilized a teacher-designed lunch card routine to initiate, maintain, and display friendships in addition to indicating their lunch selection. Findings from the study prompted changes in my instructional practices as well as in the ESL and bilingual program design at the school in order to allow greater interaction between native English and native Spanish speakers. Implications of these findings include the significance of social relationships for language learning, for gaining status, and for motivating bilingual students to remain in school over the course of their K-12 education.     

Use of the token economy system to intervene on a school-wide level

Many writers have suggested that professionals dealing with psychological problems in school settings need to consider procedures for consulting on a system level, rather than on an individual or a group level. In this report, a token economy system was implemented for all 459 students in a K-6 elementary school. Managing an intervention program at the system level required comprehensive procedures for staff training and program modification. The results showed a major decrease in classroom disruptions and a decrease in negative teacher interactions during the token economy system compared with baseline data. Data analysis the following summer on system-wide variables demonstrated that the number of suspended students and number of days of suspension decreased, that the rate of gain on achievement tests in reading and mathematics increased compared with the yearly rates suggested by test scores the previous year, and that the teacher turnover rate decreased. Several variables considered necessary for the effective implementation of the program were discussed.     

Energy balance of locomotion with pedal-driven watercraft

In this study, we examined the mechanics and energetics of locomotion with a paddle-wheel boat and a water bike. Power output (Wtot) was measured directly on the water bike by means of an instrumented chain-ring. The simultaneous assessment of oxygen uptake (VO2) allowed the computation of the "overall" efficiency of locomotion (etao = Wtot/VO2). Mean etao was 0.27 (s = 0.02), which was unaffected by the speed, and was assumed to be the same for the two boats as both are semi-recumbent bicycles. For the paddle-wheel boat, Wtot was then obtained from etao and measures of VO2. The power to overcome (passive) drag was calculated as Wd = D x v (where D is the force measured by means of a load cell when towing the boats at given speeds). Propelling efficiency was calculated as etap = Wd/Wtot, which was lower with the paddle-wheel boat (mean 0.35, s = 0.01) than with the water bike (mean 0.57, s = 0.01). The observed differences in etap and Wd explain why at the highest speed tested (approximately 3 m s(-1), the energy required to cover a unit distance with the water bike is similar to that required to move the paddle-wheel boat at 1.3 m s-1).     

Revue des revues pédagogiques de langue française

Sans résumé