- Recognize true proportions.
- Use proportions theorem in problem solving.
II.Cross-curricular-Astronomy
- Use the following map of the constellations in this activity.
- This is Figure 08.02.01
- http://www.nightskyinfo.com/sky_highlights/july_nights/july_sky_map.png
- Use the image of Ursa Major and Ursa Minor to explore the concepts of proportions.
- Are the two images in proportion?
- How can we tell?
- Complete an in class discussion on what makes two images or two ratios a proportion.
- What kinds of measurements would we need to prove that the two constellations were proportional?
- Encourage students to work with the concepts of proportions and apply it to the constellation map.
III.TechnologyIntegration
- Students can use this youtube video to study the planets in proportion.
- http://www.youtube.com/watch?v=PZNrQGCEXzs
- Students can follow this up by researching and comparing two planets.
- Have them choose two to compare and write ratios and proportions to compare them both.
- Allow time for students to share their work when finished.
IV.NotesonAssessment
- Assess student work through the discussion and through student notes.
- Were the students able to decide how to write proportions and ratios on the planets and constellations?
- Then provide students with feedback on their work.
Similar Polygons
I.SectionObjectives
- Recognize similar polygons.
- Identify corresponding angles and sides of similar polygons from a statement of similarity.
- Calculate and apply scale factors.
II.Cross-curricular-ModelDesign
- This is a great opportunity to include scale and design into the mathematics classroom.
- You can work with this lesson in two different ways.
- The first way is to have the students choose a polygon and to build a model of two polygons that are similar
using a scale model. - This way, the students can actually have a hands- on experience of figuring out the dimensions of a scale
model and then put these measurements to work building the model. - The second way is to choose a mountain or a building for the students to use to create a scale design or model
of. - For example, if you chose the Empire State Building, the students would figure out the actual measurements,
and then build a model or draw a design using a scale.
Chapter 3. Geometry TE - Enrichment