Why We’re Here:
- We’ll make our own tessellations from a hexagonal base.
- We’ll review the methods for finding area of rectangles, parallelograms, and triangles.
Materials:
- Scissors
- Index cards, pre-printed with a square and a hexagon.
- Tesselations Project sheet
The Breakdown
- Opener + Review (15 minutes)
- Demonstrate Hexagon Tessellation (15 minutes)
- Crafty Scissors Project Work Time! (35 minutes)
- Clean Up (5 minutes)
- Break (5 minutes)
- Show and Tell (1.5 minutes)
- Area Notes (20 minutes)
- Area Classwork (20 minutes)
Attachments
Slide Deck
- 54% (Times Newspapers)
- You can also use hexagons to make tessellations.
- Show how to make the cuts.
- Do you see it? Do you?!
- And do you know what’s special about The Angry Wolf?
- He’s got friends.
- Do you see the hexagons?
- Introduce the second part of the project.
- We’re bypassing any investigations here. This was a standard in, I dunno, sixth grade? So we’re just going to review.
- Show them how to build a rectangle from the pieces.
- Show them how to double the triangle to make a rectangle.
- See revisions.
Notes & Revisions:
- Should definitely have cracked some harder examples on slide 13, heavier on the Algebra. Next time give the area and work backwards to find base or height.
7 Comments
e
February 22, 2007 - 9:29 am -Do you do proofs in your geometry? In slide 6, for example, they could have proved that the area of any triangle is bh/2. The picture is there, they’d just need to put the words to it, use some triangle congruence and alternate interior angle thm. It would have been a nice exercise, I think.
dan
February 22, 2007 - 12:33 pm -Slide 6? The one with all the angry wolves? Not sure I follow. Can you elaborate?
e
February 22, 2007 - 6:25 pm -Oops. There are 5 slides with number 6 on them. The one where you write the area of a triangle; 11. in the notes.
dan
February 22, 2007 - 6:32 pm -Oh sure, yeah, okay. Y’know, the bulleted lists are not having fun inside some RSS readers. Firefox is fine, but, who knows.
Anyway, I took the opportunity to take them through an extremely informal proof of the conjecture, basically just a derivation of the formula. But I don’t think my easily-frustrated, fidgety, hedonistic high school students would’ve called an official foray back into proofs “nice.” Not by any definition of the word.
I hope that’s the difference between higher education and high school, but telling my kids, “Now let’s try a proof,” would’ve been a showstopper, I’m positive. Which is kind of a bummer.
e
February 23, 2007 - 7:51 am -So, are you saying that there are absolutely no proofs in your curriculum? Not even proofs with triangle congruence and such? What else do you do in the geometry class? Now I have to see the textbook :) As for “…would’ve been a showstopper”, my attitude is that students don’t necessarily know what’s good for them :)
dan
February 23, 2007 - 5:23 pm -Oh, no, we’ve got a unit on proofs. It’s a monster failing that I couldn’t make them enjoy proofs as much as I did when I was them.
But for me to be moving through area, building momentum there, only to break pace for a quick proof. Nah. There’s too much negative association there I don’t want to bleed all over this new topic. Maybe at the end of the area unit and, even then, only for a homework assignment.