1. recognize the properties of 2D shapes and give a correct name of each.
Example :
Cette figure est un trapèze car je sais qu'un trapèze est un quadrilatère (a quatre côtés et quatre angles) et il a aussi une paire de côtés parallèles.
I know this figure is a trapeze because I know that a trapeze is a quadrilateral (has four sides and four angles) and it also has a pair of parallel sides.
2. know the difference between "figures regulière" and "figures irregulières". The former means that a form is made of sides that are of the same length and all its angles are the same.
More info on this concept in English: https://www.theschoolrun.com/what-are-regular-and-irregular-shapes
3. use a Venn diagram to organize different 2D shapes based on their attributes.
A game to practice sorting by attributes: https://mathsframe.co.uk/en/resources/playgame/83
4. recognize and draw 2D shapes that are congruent (same size, same form)
An online game to practice this concept: http://www.sheppardsoftware.com/mathgames/geometry/shapeshoot/SSCongruentSimilar.htm
5. compose certain forms by using multiple smaller shapes (including using the tangram). For example, making a trapeze with 3 regular triangles.
Another tangram game online: https://www.turtlediary.com/game/tangrams.html
Thank you for your support.