Tuesday, May 12, 2015

Math You Can See: Art, Nature, Patterns, Society, and More


Do some reading from links below. Follow instructions on this form and fill it out for a site that interests you. If you were "invited" to join my SBAC Opt-Out class (by email to your PPS account), then when you join, you can click on the Reflections assignment, click on its form, fill in the form from there and submit it to me electronically! Cool!! It is also fine to save the form to your drive, fill it in, then share viewing privileges with me (jwright2@apps4pps.net or jwright2@pps.net), or to do a printed copy by hand and hand it in. Thanks -- I like reading about which sites interest you and what you learned!







Friday, May 8, 2015

What's the Angle? (But more interestingly: how did you solve it?)

I saw this problem on Twitter. This high school geometry teacher wanted to know what solution paths people could come up with. (He did solve it in the end himself too!)

da Vinci Geometry students: what solution methods do you see? You've given me a new appreciation for Law of Sines, so I used that; I'm curious whether you see other paths you like. Let me know and I will add them to the online discussion! (I'll put a link to that, too, eventually, but I want to see what original stuff you come up with first.)

Sunday, May 3, 2015

Geometry: Construction Project

The posters you see here (and in the da Vinci hallways) were created by my Geometry students as a way to learn, practice, and demonstrate their knowledge of constructing exact geometrical shapes, angles, and line segments using only a compass and unmarked straightedge.

Somewhere on one of the posters, each da Vinci Geometry student demonstrated how to do nine different constructions using a compass and an unmarked straightedge:

  • Copy a line segment 
  • Construct a circle 
  • Construct a triangle that is congruent to another scalene triangle 
  • Construct an angle bisector (essentially, split an angle into two evenly) 
  • Construct a perpendicular bisector of a line segment 
  • Construct a regular hexagon, regular octagon, or 30°-60°-90° triangle 
  • Construct the perpendicular to a given line through an external point 
  • Construct a line parallel to a given line and through an external point 
  • Construct a non-equilateral isosceles triangle 

If you look closely, you can see some pencil marks from their construction process!

I got the idea and some materials for this project from a teacher in San Francisco who goes by the name cheesemonkeysf online. At her blog, she wrote: “Einstein was right — imagination IS more important than knowledge. […]I created this Constructions Castle project to give students plenty of practice doing constructions while also giving them a chance to develop their understanding of how shapes and angles fit together.”

Thanks to cheesemonkeysf for the great idea and to the Geometry class for doing such a fabulous job on this project. Your posters are much more beautiful than a pile of test papers!