The study assessed whether certain features of the diagrams used to teach about Earth’s orbit can lead to misconceptions about the seasons in students (aged 14-15). In particular, it looked at the use of elongated ellipses in some ‘side on’ diagrams of the Earth’s orbit which may suggest that the Earth’s distance from the Sun changes significantly. The research was carried out by university-based researchers in the USA.

Learners’ ideas

• The rotational motion of the Earth on its axis, rather than its orbit, was considered to be most important in changing the seasons. One side of the Earth is facing the Sun while the other side is facing away from it. It would be more appropriately applied to describing the day and night cycle.
• The cause of seasonal temperature variation is the distance of the Earth from the Sun.
• Tilt-based explanations include both the scientifically accepted explanation, as well as explanations that otherwise invoke the earth’s axial tilt.
• Sunlight-based explanations do not consider the distance of the Earth, its tilt, or its orientation. Rather, solar energy is described as being directed or isolated to specific locations.
• Climate-based explanations involve a description of the seasons as a result of changes in climate or weather.

Evidence-based suggestions

• The use of elliptical depictions in orbit diagrams does not sway students strongly toward the closer–farther explanation for the seasons that have been frequently identified in the literature.
• For perspective drawings, the use of shading is influential in general as a cue for side-based explanations, but this influence can be weakened by the interposing of shapes in a perspective drawing.
• Any students who try to impose the closer–farther explanation on the drawing would fail if they consider the ordering of the seasons and are consistent in their application of any rules regarding distance and the heat transferred to it.
• Minimal intervention can cause rapid change suggesting that students’ prior conceptions, or even synthesized misconceptions, may lack contextual coherence (diSessa, Gillespie,& Esterly, 2004); that is, different mental models will emerge depending on the changing specifics of a situation.

Further suggestions

• Provide clear scaffolding concerning the key features a student should notice in a diagram. Simple acts such as pointing and gesturing around representations can do a great deal to direct attention and support the reading of visual information (Valenzeno, Alibali, & Klatzky, 2003).
• Teachers can also model by thinking out loud how they make sense of a diagram and then reconcile it with their conceptual knowledge.
• Inviting students to make public how they see and understand diagrams, through more open classroom discussions, could be productive.

Study Structure

Aims

The study aimed to test whether diagrams can influence the development of misconceptions and cause students to link the orbit of the Earth to the seasons. Six variants of diagrams depicting differently-shaped Earth orbits around the Sun were presented to students and their influence was assessed at three different points in the teaching programme.

Evidence collection

The researcher designed a written assessment including two open-ended answer responses and a space for an optional drawing to be made by the student. Students answered questions based on the use of the diagrams at three points in the teaching and these responses were analysed qualitatively and quantitatively.

Details of the sample

The sample contained 652 students (21 classes, 5 teachers) aged 14-15.