Geometry and optical illusions

Author: Daniela Leone

Methodology and tools

This is a remote learning activity, developed in March 2020 with 1st-grade students of IC21 Bologna lower secondary school.

The tools used are GSuite for Education, GeoGebra and Go-Lab resources. The activity is based on Inquiry-based Learning methodology.

Students had a little experience with GSuite, Go-Lab and GeoGebra but no experience of learning from home. To be able to communicate we used GSuite tools (email, tutorials on Google Classroom, Google Meet calls).

The Go-Lab Inquiry Learning Space used for the activity is a translated version of the French ILS “Changer de perspective” created by Valentin Roussel.


Thanks to the author, the ILS was useful to guide students in discovering basic geometry in a playful way: it aroused their curiosity about the features that add special effects to images. The questions helped students to reflect and recognize the main properties of parallel and perpendicular lines, angles, areas, by manipulating dynamic figures. The images included in the ILS were inspiring for students.

At the end of the translated version made for the IC21 school, I added an extra task for my students: they were asked to make and share their own images containing optical illusions or special effects, using the GeoGebra Geometry App. 

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