Teaching Weight-Gravity and Gravitation in Middle School

This study deals with the school instruction of the concept of weight. The historical review reveals the major steps in changing weight definition reflecting the epistemological changes in physics. The latest change drawing on the operation of weighing has been not widely copied into physics education. We compared the older instruction based on the gravitational definition of weight with the newer one based on the operational definition. The experimental teaching was applied in two versions, simpler and extended. The study examined the impact of this instruction on the middle school students in regular teaching environment. The experiment involved three groups (N = 486) of 14-year-old students (ninth grade). The assessment drew on a written questionnaire and personal interviews. The elicited schemes of conceptual knowledge allowed to evaluate the impact on students’ pertinent knowledge. The advantage of the new teaching manifested itself in the significant decrease of the well-known misconceptions such as “space causes weightlessness,” “weight is an unchanged property of the body considered,” and “heavier objects fall faster”. The twofold advantage—epistemological and conceptual—of the operational definition of weight supports the correspondent curricular changes of its adoption.     

Designing and implementing authentic investigative proportional reasoning tasks: the impact on pre-service mathematics teachers’ content and pedagogical knowledge and attitudes

In this study we created, implemented, and evaluated the impact of proportional reasoning authentic investigative tasks on the mathematical content and pedagogical knowledge and attitudes of pre-service elementary and middle school mathematics teachers. For this purpose, a special teaching model was developed, implemented, and tested as part of the pre-service mathematics teacher education programs conducted in Israeli teacher colleges. The conclusion of the study is that application of the model, through which the pre-service teachers gain experience of and are exposed to authentic investigative proportional reasoning tasks with incorporation of theory (reading and analyzing relevant research reports) and practice, leads to a significant positive change in the pre-service teachers’ mathematical content and pedagogical knowledge. In addition, improvement occurred in their attitudes and beliefs towards learning and teaching mathematics in general, and ratio and proportion in particular.