Water & Buoyancy Science For Kids, Montessori Physics Part 2

Welcome to part 2! We are having great fun exploring water! 

This experiment is very popular, but it does happen to be in our Science Book of Water. We created a diver with a pen cap, a little bit of modelling clay, a two litre bottle, and water. 
The air trapped in the cap keeps it buoyant - when you squeeze the bottle it creates pressure, and forces more water into the cap - it becomes less buoyant thus sinking to the bottom. 
Xander thought it was pretty cool that he could control the depth of his little cap diver. 
Our book gives a great explanation, and chats about the function of submarines. 
This is a great layout for this experiment  if you have not tried it. 

Testing his cap in a glass of water.  He had to adjust the amount of clay a couple of times.

Ava added a cap in also and he tried a little feet action:)

We talked about Buoyancy, Negative Buoyancy, and Neutral Buoyancy. 
Ava is checking in here.  She spent a great dealing of time with her own tray, water pouring, and with sink/float activities 😃

We started this experiment talking about the Archimedes' Principle - Discovery of Water Displacement & Buoyancy.   
We used a kitchen gram scale, and measured out a lump of clay. 

He placed a glass bowl into a glass pie plate, and then filled the bowl just to the overflow point. 

Then he dropped in the clay.

He measured the amount of displaced water.  He found that while it was close in weight, it was a little difficult with such a small object (given our method and instruments in use).

So we tired a larger glass bowl repeated and submersed it in the water.

This time he poured the displaced water back into the bowl to see how close it was, you can see above he was very pleased with the result.

Lego always finds it's way into everything we do 😃

This is another experiment found everywhere.  Here we were talking about ships and buoyancy.  Xander created a clay ship.  We talked about characteristics as to what would make a ship sink or continue to float. 

We talked about weight restrictions and weight distribution.  For this experiment we used a large glass marble, and a clay ship.  He placed the large marble in the ship, and observed what happened.  Then we had a chat about why the ship sank. 

We chatted about how his body floats on the surface of the water, if his weight is evenly distributed over the water.  Was there a way to evenly distribute the weight of the marble to see what would happen?

Xander figured out that 4 small marbles had the same weight as the larger.

He placed the marbles evenly in the boat, and it did not sink!!! 

Very exciting stuff!
Then he put the ship in a sink of water, and created waves (stormy weather).  He came to the conclusion that ships could only safely carry a certain amount of weight. We talked about the phrase 'batten down the hatches', and he tried to make a clay cover/seal for his ship to keep it afloat.

We watched Bill Nye - Buoyancy Episode again... and again... and again:)
If you missed it...our Water & Buoyancy Part 1
From here we will meander into our Montessori Research and Development Chemistry manual, to explore water even further.

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  1. Thank you so much for sharing this awesome experiment in such detail! What an amazing learning opportunity for child!! Looking forward following your posts!

  2. Thank you Anastasia!! We are having great fun with this unit:))

  3. What a great post! Love the science experiments! They are so under appreciated! G+ and pinned and tweeted!


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