Science Club: water

Today was my first visit to Brookvale School for the new school year. I had a new contact teacher there, after the teacher I worked with last year moved to another school. The new teacher organised a timetable for me, giving talks to the kindergarten and Year 1 and 2 classes, and also a 1.5 hour session with the new Science Club, for which she chose the students.

With the K-2 classes I gave a talk about the many different sorts of things that scientists do, including medicine, studying animals and plants to learn how they live, looking at rocks to work out where to dig for useful minerals, measuring volcanoes, drilling in ice to study the atmosphere from hundreds of years ago, astronomy, building robots, and making computer models of things. They all seemed fascinated to see all these different things, and the talk went pretty well.

For Science Club, the teacher initially gave me a list a few weeks ago, of 12 students. Only three of them were in the Science Club last year, so she’d clearly decided to give some new children a chance to participate. Then late last week she emailed me and said there were six other kids who were super keen to be in Science Club; would it be okay with me if they joined in? I said that would be okay.

I got there today, with a print out of the initial timetable the teacher had sent me, with the names of the original 12 students, but not the new six. As the kids filed into the library after recess, I asked them all their names, wrote name tags for them to wear so I could learn them, and also wrote down the names on my list.

I told them what sorts of things we’d be doing in Science Club, and then we started on some experiments. Today we were looking at properties of water. First up was looking at surface tension. I used an eye dropper to put drops of water onto a 5 cent coin on the floor, producing a bulging bubble of water, held on by surface tension. We counted how many drops I put on, before the bubble spilled and wet the carpet.

I explained to them how water was made of molecules of hydrogen and oxygen, and how the H and O atoms like to stick together, making an elastic skin on the surface of the water. Then we repeated the experiment, but with soapy water. This time the bubble was smaller, and I added fewer drops to it before it spilled. I explained that the soap had large molecules with one end that liked to stick to the water, but the other end pushed the water away. This made the skin weaker, explaining why the drop couldn’t get as large.

Next we did another experiment to look at surface tension. I filled a plate with milk and added drops of food colouring to the middle of the milk puddle. Then I got a cotton tip and dipped it in liquid soap… and touched it to the middle of the plate. I took a video:

Satisfying!

Next I got two glasses of water, one hot and one cold. I dropped some food colouring in each one, and we watched how it mixed into the water. In the cold water, the colour sank to the bottom and formed a layer below the clear water. In the hot water, however, it mixed evenly throughout. Then I explained to the kids that hot temperatures are caused by the molecules moving faster inside the water, and the faster moving molecules mix the colouring faster.

Finally we did an experiment in which I mixed iodine solution into water to make a brown liquid, and added some baby oil to form a clear layer on top. Then I shook the bottle to mix it all up, which encouraged the iodine to move from the water to the oil, in which it is more soluble. Doing so changes the colour to a bright purple, because the iodine colour depends on which liquid it’s in.

After a full day, I went home to relax. I typed out the names of the kids who I’d written down to send to the teacher, as a roll call. Then I noticed that the other timetable sheet she’d given my first thing this morning had the extra six kids’ names on it…

And the list of names I’d written down had three names not on that larger list. There were three extra kids in the Science Club who weren’t supposed to be there! I’m not sure if there was some sort of miscommunication, the kids thought they were in Science Club when they weren’t, or what happened. So I let the teacher know, and we’ll see what happens next time!

New content today:

One thought on “Science Club: water”

  1. aside from funding issues, any kid interested in science should be encouraged – too many prefer to oppose it these days that it’s really important work – what you’re doing with these kids.
    Also – pretty experiment…

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