1. Geogebra is a dynamic mathematics software program for learning and teaching mathematics and science from primary school up to university level. Constructions can be made with points, vectors, segment, lines, polygons and functions. We use this software with our students.
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2. This is the Geogebra home screen

3. Every icon represents a set of comands, in fact, if you click with the cursor on one of these icons a drop–down menu opens on which it is possible to choose the useful elements for geometric constructions : point, straight line, segment, polygon, circumference.

4. For example: if we want to draw a regular polygon, we click on the fifth icon (Polygon), we choose the item Regular polygon
We draw the AB segment that represents the side of the polygon

5. Consequently a window in which is inserted the number of the sides opens...
...so Geogebra automatically draws the polygon

6. We want to trace the heights of a triangle
We draw the triangle
We choose the perpendicular line button, we click on the point A and on the BC segment.

7. Automatically Geogebra will draw a perpendicular line that represents the height of the triangle
We will proceed in the same way for the other two sides.

8. We use Geogebra with the interactive whiteboard and the students with their personal smartphone.

10. This is an example of lesson carried out in the classroom