We present the development and validation of a new assessment tool, the Moon Phases Concept Inventory for Middle School (MPCI-MS), a concept inventory about the phases of the moon targeting students aged 10 to 14 years old. Items in the questionnaire are based on a careful examination of the concept domain of phases of the moon, ideas and concepts…

This article describes a unit in which students investigate total solar eclipses, such as the one coming August 21, from several perspectives. It incorporates mathematical thinking and aligns with the "Next Generation Science Standard." This article refers to physical, virtual, and mathematical modeling. Various models and perspectives…

Empirical studies have reported difficulties, confusion, and lack of understanding among students at all levels of instruction regarding the issue of weight--gravitation--weighing relationships. This study examined the impact of a new conceptual framework of weight, on a small group of 7th-grade students (N?=?14) in a middle school in Israel. This…

Students' difficulties with accurately conceptualizing the relationships among the Earth, Moon, and Sun are well documented. Any teacher who has seen the film "A Private Universe" (Schneps and Sadler 1988) will remember the challenge the interviewees experienced when trying to explain their understanding of this phenomenon. This paper describes a…