Skip to main content
Recently I helped Luke's classmates make geodesic domes out of newspaper, using this website:
http://www.pbs.org/wgbh/buildingbig/educator/act_geodesic_ho.html
It was very satisfactory: the kids learned about the importance of measuring accurately, keeping track of progress, and how something that looks unimpressive to begin with can be actually amazing at the end.  I was even amazed ("It works!  Math works!" I exclaimed as the kids put the roofs on) and I've done it before.

To give the kids something to look at, we made a sturdier but smaller dome out of straws. I used this website, which has a mix of complete, accurate directions and pictures and vague, inaccurate directions, as well as nice pictures of a chicken run geodesic dome:
http://sci-toys.com/scitoys/scitoys/mathematics/dome/dome.html

One important note: you actually need the following numbers of straws:
  • 90 long (7 3/4") straws, for 6 pointed stars
  • 50 short (6 1/2") straws, for the 5 pointed and partial 5 pointed stars at the bottom, and 
  • 70 medium (7 1/2") straws for connecting the edges of these stars.

The other things that are helpful is to realize that any 5 pointed star could do for the top---so to continue the design, make all the 5 pointed stars have the same configuration around it.  It also helped to look at his paper domes: those were much easier to figure out due to their color.

So here is an attempt at a picture of our dome, rather the worse for wear from being played with by elementary school children.  You can see that it really is sturdy, though: after going through through a couple car rides, being used as a tree topper, being squished through doorways (it actually goes through sideways quite nicely) and the aforementioned children, it still has its characteristic shape.

Comments

Popular posts from this blog

My hero, Helen Parr

Otherwise known as Elastigirl , a.k.a Mrs. Incredible. She is a stay at home mom ( SAHM ), she clearly feels that what she is doing is important and is willing to give up a lot to do it (remember her comment in the intro: "I'm at the top of my game! Leave saving the world to the guys? I don't think so.") But she is finding fulfillment in leading her family from day to day, in doing a hard job well. She also knows that she is very talented, and that knowledge helps her see beyond the repetitive drudgery of staying home. My favorite scene is from the deleted introduction, where she talks with a "career woman" who is of the opinion that staying home is fine for people who can't do anything else. She responds that taking care of her kid is at least as hard as saving the world, and is valuable contribution to society. The point for me is that someone has to do the job that I'm doing, and it's not something that you could pay someone to do. I see...

Things that are true

"Axial tilt is the reason for the season." (Picture a globe with the northern hemisphere tilted away from the sun...) I believe this is meant to be an anti-theist slogan, although I would point out that I believe there is a reason for the axial tilt. This is a runner up to my favorite true science picture, the "Gravity Forecast." I linked to this when I was a graduate student, but the site is long since down. Picture a weather forecast graphic, but instead of clouds and temperatures, the 5-day forecast predicts 9.8 m/s^2 down. Even the idea still makes me laugh, perhaps I will reproduce it someday. Luke cut his 4th tooth today (Finally!). So far they haven't caused us too much trouble. We'll see what happens when he gets his canines.

Why the world is frustrating

It is very frustrating to be 2. Michael and I have been teaching Luke about closing doors and turning off lights---both good habits. He really enjoys opening the refrigerator door. He knows how to turn out the light. But when I try to get him to shut the refrigerator door, he screams, "Turn out the light!" He keeps getting in the way of the door so that he can push the little button. As far as I know, he's trying to turn off the light before we shut the door, and the fact that it keeps coming back on when we move him out of the way so we can shut the door drives him crazy. He doesn't believe us that the light goes out when the door is shut, and after all, how do we know ourselves? We've never seen it, we use logic. But this makes any attempt to shut the door a battle, unless I sneak over there without him seeing.