Floating boats

We had a great time talking about boats today.
We have already looked at things that float and things that sink.
The big shell surprised us; it was big and heavy but it floated fine.
Teacher gave us each a sphere of marla.
We found that it sinks.
Now we tried making this marla into a floating boat.
It was quite a challenge, but we did it in the end!

Next we competed to see how many passengers each boat could safely hold.
We recorded and then compared results.
Our best boat could safely hold 28 passengers!
When every pair had a turn we lined up the boats according to the most passengers each could hold.
The most interesting discussion of all was the one in which we tried to find out why some boats won't float at all.
We decided that it is best to have a boat with a thin bottom, high sides and  no holes.
When we fixed the sinking green boat so that it became a boat with a thin bottom, high sides and no holes it floated very well.
Now that we are such expert boat makers we each made a boat out of clay.
We know that these will not float (because the clay absorbs water) we went about making our favourite kinds of boats.....submarines, boats to hold snowmen, boats with sails, cruise ships etc.
We are really interested in boats now!