In this study, the researchers designed a set of ‘innovative’ astronomy images concerning seasons, lunar phases and eclipses. Students were placed in groups, some using the traditional textbook diagrams and others using the new diagrams. Their understanding after use was then assessed quantitatively and the groups were compared. The research was carried out by university-based researchers in Italy.

This paper clearly provides a detailed examination of some traditional uses of simple astronomy diagrams in textbooks. It raises interesting questions about the appropriateness of these and provides a possible template for the study of diagram use in other areas of physics.

Learners’ ideas

• The idea that Earth is closer to the Sun during summer
• The Earth does not face the Sun during winter
• The Earth or the Sun cast a shadow over the Moon (for moon phases)
• Confusion over lunar and solar eclipses and what is blocking the light in each case

Evidence-based suggestions

• Elements in images used in traditional textbooks can interfere with student understanding and lead to incorrect ideas.
• The innovative images about seasons likely succeeded in helping students grasp the relevance of the orbital motion and of the tilt of the Earth’s axis.
• No effect was detected from using the innovative images over the textbook images for Moon phases and solar and lunar eclipses, but there was a slight benefit to using any images over no images.
• Students who produced drawings with iconic features that could suggest an understanding were not able to give correct written explanations. Such a result is in line with prior literature that suggests caution in using drawings to elicit misconceptions or as an assessment tool.

Study Structure

Aims

This study examines to what extent usual textbook images influence students’ understanding of phenomena related to seasons, lunar phases and eclipses. It introduced innovative diagrams and sought to assess their effect on understanding in 13- to 14-year-old students.

Three research questions were asked:

1. How are students’ explanations and visual representations of familiar astronomical phenomena affected by different image-support conditions?
2. How are students’ conceptions about familiar astronomical phenomena affected by different image support conditions?
3. Which features of the used images most affected the students’ visual representations and explanations of familiar astronomical phenomena?

Evidence collection

The questions were investigated through a range of methods:

• a drawing task, during which the students were asked to make a drawing that would explain to a reader the change of seasons, Moon Phases, and solar or lunar eclipses
• a written task, in which the students were asked to give a written explanation for each of the three phenomena
• a mixed multiple-choice and true-false baseline questionnaire featuring 24 questions

Students’ drawings were analysed using exploratory factor analysis of iconic features [Libarkin et al, Factor analysis of drawings: Application to college student models of the greenhouse effect. 2015], which allows us to identify emerging representative student models. In total, approximately 2000 pupils’ drawings about seasons change (494), Moon phases (539), and solar(427) and lunar eclipses (499).

Details of the sample

The sample consisted of 31 girls and 37 boys, aged between 13 and 14 years.