For the last few weeks our class has been learning about the lovely and very interesting work of Claude Monet. The children have been especially interested in works containing the Japanese bridge.
After a few weeks of study about Monet (and his bridge), I challenged the children to look at an arch from a different point of view. This time I asked them to look not with the eyes of an artist, but with the eyes of an engineer!
Why did Monet choose to make his bridge an arch shape? True it is a lovely and graceful shape, but with all the different bridge shapes in the world, why this one? What is so great about an arch anyway? I am blessed enough to have a parent in my class this year who is an engineer. She kindly came to visit our class to help us figure out . . .
What is so great about an arch anyway?
Well, an arch is SUPER STRONG! It has this strength because of compression. Mrs. A-L showed our class an easy way to see how this works.
She laced the fingers of her hands together and held them flat under her chin. Then she rested her chin on top of her fingers. What happened? Her fingers broke apart!
But when she laced her fingers together and made them into an arch shape . . .
she could have rested her chin there all day!
Mrs. A-L showed us some photographs of arches that have been around for a really long time. I told the children these arches had been around since before I was born! WOW! That means they have been around a really long time! Of course the children asked if the arches had been around since before the dinosaurs. I said they (and I) hadn't been around quite that long.
Of course, Mrs. AL was referring to some arches made by the ancient Romans.
Like this . . .
I asked the children if they could think of any arches they had seen around their homes or around our school. Then I asked them if they had seen any . . . in their refrigerators! Hahahahaha! They thought that was a silly question until I pulled out an egg.
What shape is the top of an egg?
The children agreed that it was an arch. But then I said, "Wait, but eggs are so fragile! If you drop it, it breaks! How could it be fragile and strong at the same time?"
I did an experiment with the children to see how strong the arch of an egg really is. I found this experiment years ago, in a book I have from The Exploratorium in San Francisco. The book lists Science Snacks. I can't find this experiment on their current web site, but it is explained very well here, at the web site of the San Diego Zoo.
With the children, I carefully placed an egg in a section of egg carton. Then I placed a block of the same height opposite it. We guessed how many books the egg and the block could hold before the egg broke. The children's guesses ranged from 2 to 10000! I carefully began placing books, one at a time, on top of the egg and block. I used exaggerated care and facial expressions. I successfully placed 6 books on top of the egg, and then it began to crack! The children began shrieking! I placed on 2 more books totalling 8, and with the addition of the 9th books, the egg broke! The last time I did this experiment, it took 23 books! Maybe I had an old egg this time, but it was still wonderful to see the amazement on the children's faces!
The only problem with this experiment was that the children didn't get to participate. I don't know what I was thinking, but if I do it again next year, I will do it outside and let each child try it out for him or herself!
Here is another egg experiment to try out. It looks fabulous! Click on the picture to go to Steve Spangler's "Walking on Eggshells" experiment.
After we did the egg experiment, Mrs. A-L showed the children some other arches that occur in nature. She had a book with fabulous photographs. One of them was of a shell like this . . .
See the arches? The children did too!
After that Mrs. A-L brought out a gift she and her family had made for our classroom! It was 4 sets of PVC pieces with stands, for the children to make their own arches! The children went to work immediately, building away!
And of course, we had to use the arches to make a rainbow fort.
After the weekend, we went on an "Arch Walk" around our school, looking for arches. The children found so many! I made an "I Spy Arches" book (from the photographs that we took during the walk) so the children can revisit arches outside of the classroom, anytime they wish to do so.
And my daughter kindly loaned me her Curvy Board!
The children experimented with an arch rocking . . .
acting as a back stretcher . . .
and as a bridge! Sorry, this isn't Monet's Japanese bridge. It is the troll bridge from The Three Billy Goats Gruff. See the troll under the bridge?
How do you create bridges between disciplines?
Feel free to post a link in a comment so we can share bridging ideas! Thank you!