While we were on vacation, we worked our way casually through Shining Dawn’s Hard as a Rock unit study.
The island where we have our cottages is in the middle of one of the Great Lakes and, as you can imagine, is a treasure trove of rock formations and alvars (flat areas of land entirely covered by rocks).
Here are a few things we did (saving any other suggestions for a follow-up next year – every unit has more than enough ideas to do it twice and never repeat):
We went for a hike at the creek nearby. In spring it’s about 3 feet deep; in July it’s bone dry except for a few very frog-filled pools near the beaver dam. K and my husband wandered off to climb the dam. They may or may not have been singing the Lumberjack song from Monty Python as they went "leaping from tree to tree" on the way.
while M, D and I looked at the rocks in the dry creek bed to see how water had shaped the stone.
We became distracted by frog-catching after a few minutes. I have never seen so many frogs, of so many varieties, all in the same place before. Every time you took a step about 30 leaped into the water.
K returned and started checking out what was under the rocks in the creek: surprisingly few creatures there.
We collected pebbles on our own beach and tried to guess what they were (sedimentary, metamorphic or igneous).
Chain coral,Colonial coral, Shells,
And a mix of all kinds of things all on the same rock.
We also saw the variety in the rocks themselves. Manitoulin Island is made up mostly of sedimentary rocks like shale, but because of a volcano further away about 10,000 years ago, causing the 3 feet of ice that used to cover it all to slide, there’s a good mix of metamorphic and igneous rocks as well.We also learned that the cracks in the alvars were from expansion underneath caused by the same volcano.
We marvelled at how plant life will grow anywhere it can get a grip.
This is the gravestone of the man who built our cottages, and whom I had the pleasure of knowing as a child. Meet Ivan Bailey and his wife “Dot”. Ivan’s parents, Isaac Bailey and his wife, were reportedly the first non-native settlers on the island.
The other stones were people we knew as well, or know their adult children (it’s not a big graveyard, or a big township) but mostly we looked respectfully at all the beautiful rocks that had been chosen for the headstones and discussed the thought that must have gone into choosing them.
This also led to a discussion/debate about whether granite is metamorphic or igneous, with votes pretty evenly divided. In case you wondered too, according to WikiAnswers (http://wiki.answers.com/Q/Is_granite_a_sedimentary_rock_metamorphic_or_a_igneous_rock) they are igneous but the WikiAnswers people do a nice job of explaining the confusion.
On another day, we went back to Misery Bay and took our little sieve thingies and some coffee filters. Each of the kids sieved out the sediment at a moving water source at the shoreline, and spread it out onto coffee filters.
Then we took guesses as to which one was the oldest. Our conclusion was that the all-rock one was oldest because the vegetation had already rotted away and left only the pebbles.
On our way home again at the end of the month (sniff, honk) we looked at all the layers in the cliffs that line the highway.
Next up will most likely be (shudder) Spectacular Spiders since they’ve all been gorging themselves on the mosquito population and should be suitably big and hairy for viewing….I can’t even finish that thought without making my skin crawl! I will most likely be directing this next study from a safe and hopefully spider-free distance.