Think: Rocks, rocks, rocks

Think! Challenge: Rocks.
Choose 7 rocks of different shapes and sizes, all two inches or larger. Build the tallest tower you can build.

We're a little behind on the Think! challenges, what with snow, and holiday projects and outings, and tummyaches. But this challenge was fabulous, well worth doing just for fun. We weren't able to go outside to choose our rocks. Rocks over two inches in size are in short supply around here, and it's too cold outside to go digging around for rocks anyway. As luck would have it, we'd collected rocks on our last outing to the beach, and the boys had a rock collection in a small box, so we were able to track down nine large rocks. The fine young gents started out measuring all of the rocks to make sure the rocks were larger than two inches, which led to a discussion of how to measure sizes: Does it have to be taller than two inches when sitting on the table? Or does it just have to have a surface longer or taller than two inches? They decided that if they could find two inches of rock, it didn't matter if it was a long flat rock or a round rock. Lovely problem-solving there.

We had some challenging shapes. Knowing nothing about rock-building, it took me quite some time to build the structure above. I didn't measure it, so I have no idea how tall it is, but I dealt with quite a few tumbles before I was able to get a tower that stayed up.

Calvin's first completed structure was about 6-1/2 inches. He continued building, but wasn't interested in measuring his other structures.

The challenge he was most interested in was self-imposed: How to make a rock bridge. The two gents worked together on that puzzle for quite a while.
Lovely learning opportunities in this challenge:
Vocabulary--balance, stability, convex, concave, wedge
Engineering--how surfaces fit together, finding ways to stabilize a structure, building different structures with the same materials
Persistence--how to maintain a positive attitude when your structure keeps tumbling
Teamwork--working together, listening to the ideas of others and incorporating them into your own
Fun!
Look at that smile! Tolly built a 4-1/2 inch structure. He was just interested in building something that would stay up. He also spent a long time building new towers and bridges once he'd measured his first structure.

The challenge for me: Knowing that if only he'd try this or that, he could make his structure taller. But, as with his brother, getting the tallest structure possible wasn't as important to him as it was to his rule-following momma. He enjoyed the building and the measuring. He was happy with his final structure.

A good challenge inspires thought, fun, and variation. We only had one set of large rocks, so while his brother built with rocks larger than one inch, Tolly built with the rejected smaller rocks. He had a grand time measuring and knocking down his small towers.

While these fine young gents worked on their rock structures, their youngest brother built block towers and knocked them down. I'd intended the Think! activity as our morning warm-up, thinking fifteen, twenty minutes. By the time we were all done building, more than an hour had passed, and the rocks were left out for three more days so that the boys had a chance to build and rebuild and rebuild again. Lovely!

Consider trying this week's Holiday Challenge: Build a tree! It looks like fun.