I don't know WHAT my issue is with these geography experiments. THIS time I practiced most of this beforehand like a proper Montessori guide should. I'm glad I did or the boys would have sat through a few failed attempts. SOME of this went very well. I have a video for each demonstration.
First we want to show the children that wind moving across water causes the water to move in the direction of the wind. We sprinkle sawdust across the surface of the water as a vehicle by which to see the movement of the water.
Next, we place an obstacle in the water so that we can see that some water will move around the obstacle and some water returns.
So far, so good. We followed up by looking at our impressionistic chart that shows the ocean currents and we observed that some currents went around obstacles and some returned. The chart was from the KotU album. The ETC chart showed so many currents and in a way that made it hard to read. The KotU chart was simpler and looks something like this without the labels that name the currents (you use that later on):
For Demonstration Two the instructions said "Place the flask in the pie tin on the heat source." I thought, "What flask?" So, I looked back at the supply list and under demonstration two it says, ""Flask of water with sawdust mixed in (can be the same flask from the first demonstration)." There was no flask in the first demonstration. What kind of flask? Anyway, it also says, "insert the saw dust in the flask before the water so it settles to the bottom."
It is a good thing I practiced. I decided to use an Erlenmeyer flask because I didn't think they meant a hip flask (I mean, the moon can cause currents but not moonshine) and it was the only other kind of flask I could think of. I dutifully put in the sawdust and then gently the water and....the sawdust floated. I thought, "maybe it will sink overnight." So, I went and checked the tray from demonstration one which had sat out overnight and, nope, the sawdust was still floating. Then I thought, "Maybe it's because we have very fine sawdust and they mean more typical flaky sawdust/shavings." So I emptied our pencil sharpener into an empty Erlenmeyer flask and slowly added some water. It floats. Hmmm. So then I tried cornflakes. They may sink in a bowl of milk at times but not in my flask of water. Then I tried Smart Bran. Floats. Finally, I tried popcorn. Sank!
Next I was wondering about this pie tin. Why would I put the Erlenmeyer flask on a pie tin instead of directly on the bunsen burner, or in our case, stove burner? So I went rogue and put the flask on the burner. We lived. Kal-El was concerned the popcorn would pop but it was fine.
Finally we show the children what happens when currents of different temperatures meet. We examined our chart of the currents and noticed that some cold currents seem to disappear when they encountered a warm current and reappear later and wondered why. What happens when a cold current meets a warm current?
I prepared a clear bowl of very hot, almost boiling, clear water. I also prepared a beaker of very cold water with ice that I tinted blue. The instructions say to add the cold water very slowly to the warm water pouring just inside the edge. The cool water is supposed to go to the bottom, and you can see in the video that it did. However, in person it just looked an awful lot like the water slowly turned blue. I think if you do this with your children you should be sure they bring their eyes down to the level of the bottom of the bowl. Fortunately we were able to watch the video afterward and see it again from the lower perspective. Also, the longer I pour the less effective the demonstration is. Just some tips.
I think they are doing a similar demonstration here at Montessori Messy, but I can't really tell from the pictures and description exactly how it worked or what happened. Apparently reading these types of experiments out of a book is my personal Kryptonite.
The blog All Things Beautiful which isn't quite a Montessori blog but borrows from a lot of Montessori activities did a seven-part series on ocean currents with different demonstrations. I highly recommend it. The boys are very interested in this so we'll probably expand this topic and do these. Also, I plan to segue here into the expeditions of Thor Heyerdahl and the book Kon-Tiki (affiliate link and one of my husband's favorite books of all time). And by "very interested" I mean Kal-El said this to me an hour ago: "Mom you totally rocked those ocean current demonstrations today. You are really good at picking what we do." Sorry Jessica, I went ahead and took full credit for this in his eyes. I didn't think you would mind.
Ocean Current demonstrations at All Things Beautiful:
I: Surface Currents
III: Temperature Currents
IV: Polar versus Tropical Water
V: Ice Cubes Demonstration
VI: Layering Liquids
VII: Explorers and Ocean Currents