This is a self-directed worksheet for discovering the properties of parallelograms. The worksheet uses an applet that has already been created in Geogebra to help students explore. IMPORTANT: Students do NOT need to create the figure in Geogebra themselves - it has already been created for them. Also, there is no need to download the Geogebra program - students simply to to a website and explore the parallelogram on the website. The instructions tell students what to click on in order to answer the questions.
After the students explore, the teacher will want to have a whole-class discussion to talk about what students found. One student might discover something that no one else noticed. Students should be allowed to share their discoveries with their peers, without criticism from the teacher.
The answers on the answer key are sample answers. It is important to be prepared for answers other than those that are listed. For example:
For Question #1, students might write, “The angles facing each other are equal,” or “Two angles are equal to each other and so are the other two.”
For Questions #2, students might describe the position of the sides – “The top and bottom sides are congruent and the right and left sides are congruent to each other.”
Be prepared to guide students on how to describe what they are noticing in the most mathematically sound way.