Geometry in the sand

Joseángel Murcia

This is a guest post by Joseángel Murcia of TocaMates, translated from Spanish by Ever Salazar.

Sand has always been a good place to do geometry. In fact, ancient Greeks used it instead of the “modern” blackboards to show their ideas and schemes. It is also said that Archimedes died while drawing in the sand from the beach, disobeying a Roman order to stop.

At the beach, we can do lots of designs, but today we will focus on two ideas.

Sand Spiral

Ages two to five

What can we make? Sand polygons
How can we make it? Using a stick, draw a “path”. The kids should follow it. The paths can be curved lines or straight lines (forming polygons), they can be left open (with exit) or closed (to follow indefinitely, around and around).
Why make it? It is about experimenting with polygons, lines and angles. It is about feeling geometry in our bodies.

ElipseDeJardinero

Five and older

What can we make? Gardener’s curves
How can we make it? We will need two large sticks in the sand, like poles from the beach umbrellas. Use those when sun is down, and they are not necessary anymore. We will also need a rope and another stick to draw the curve. Tie the rope to the two sticks so it has some slack. Pull the rope taut with the third stick, to form a triangle. Now draw with that stick, keeping the rope taut at all times. Changing the distance between the fixed sticks (the focus), we will get different ellipses. What happens if we put both sticks together and have only one focus?
Why make it? Conics (like ellipses) are known from ancient times. Those from the sausages are my favorites!

SausageEllipse

This post is from a series of everyday life activities to help kids (and grown-ups!) to discover how to look at the world with math eyes. They were published as “Mathematics is for the Summer” in “Today’s Women” magazine.

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Posted in Grow

Isobel’s thoughts on the Universe

Ask your children what they think about the life, the universe, and everything. Amazing stories can unfold. Here is what one seven-year-old has to say.

Isobel R.

 

~*~*~*~*~*

Here’s how I came up with this theory. I saw the globe and was wanting to go on vacation and then I thought they should have a map of the universe but then I thought it would be impossible. But then this theory came to me. Since the universe doesn’t have an end it must be a sphere and that is why no one has ever reached the end of it.

You know a tube of toothpaste with toothpaste in it? Well, it might be like the universe with all the planets in it and the universe might be shaped like a sphere and part of something bigger. Just like the tube of toothpaste is part of our bathroom which is part of our house which is part of our town which is part of our city which is part of our country which is part of our world which is part of outer space. So, those images get bigger and bigger just like the universe is in something bigger.

Maybe our universe is just a galaxy drifting in another universe that we do not know the shape of, but I think it is shaped like a sphere.

Isobel and the universe within another  universe

See the solar system almost in the middle? Well, that’s ours. And that sphere is holding all the planets and asteroids and whatever is in space. That sphere is our universe inside another universe and that’s what I think is there.

~*~*~*~*~*

We need kids in adult communities – for inspiration! The story above sparked a big conversation (70+ comments; Facebook login required). People discussed hyperspheres, the curved space theory, the shape of the universe, measuring left-over background radiation from the Big Bang… And looked at pictures and stories from sources like NASA.

Shape of the Universe

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Posted in Grow

Playing, dreaming, translating: Newsletter May 30, 2013

Subscribe

I am Moby Snoodles, and this is my newsletter. I love to hear from you at moby@moebiusnoodles.com

Moby Snoodles

Book news

Friends of the project are starting translations of Moebius Noodles into French, Turkish, Frisian and Dutch. If you can help with these languages, join our crowd-translating hub: http://crowdin.net/project/MoebiusNoodles We will copyedit translations and release them under Creative Commons open licence, just like the book.

Ask Moby Snoodles

There are a few new questions up at the Q&A hub. Check it out!


Read more ›

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Free to Learn by Peter Gray: Review and Infographics

“GO TO HELL.”

Peter Gray’s book starts with a bang – Peter’s son curses his parents and educators. Peter and his wife are crying: “This time I felt, maybe, I really would go to hell.” What would send him there? The book explores the dire consequences of forcefully educating children.

(Click the images to enlarge them.)

7SinsOfCoerciveEducation

How can we stop being complicit? The book offers several answers to this question, including modeling one’s education after hunter-gatherers tribes. Kids can find the resources to live freer lives within modern tribes, such as techie start-ups, unschooler circles, and maker communities.

7BenefitsOfOpenEducation

One of the benefits of open education is free age mixing, a topic large enough to warrant its own map.Value_of_free_age_mixing

Peter Gray presents a five-part definition of play strikingly similar to math. It is useful for those into game design, experience design, curriculum design, and parenting.

Definition of Play

There is a math club activity where students make “star diagrams” out of lists of what is important to them. Here is such a diagram explaining Peter Gray’s five types of play as they relate to math.

Types of Play

“Free to Learn” explores two venues of open education. First, democratic learning communities in freeschools such as Sudbury Valley or Reggio Emilia. Second, a style of trustful parenting and homeschooling called “unschooling” where individual families walk their own paths. Both provide the benefits of open education presented in the diagrams above.

Reading Peter Gray’s analysis of the two methods, the drawbacks are clear. In freeschools, resident teachers do not pursue their professions so that they can help children full-time. This leads to a situation where kids are rarely exposed to the projects of adults. Unschooling families can provide exposure to grown-up work. However, it is harder for individual families to maintain ongoing daily contact with a large multi-age group of kids.

Why not the benefits of both paths without the drawbacks? We need something beyond freeschools, and beyond unschooling. Let’s get to work!

 

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