Why don't cargo ships sink?

Back to the misconceptions of young minds about floating and sinking: heavy things sink and things made of metal sink.  How then do cargo ships ladden with tonnes of cargo stay afloat?  We tried to build our own cargo ships.  The criteria was that the ship must float and that the cargo should not mix together.  Here's the list of the cargo each ship was to hold.

In pairs (to allow for conversation to confirm ideas) the students planned what they were going to construct.

Students are often paired to ensure that they have someone to discuss their thinking with.  If a student can discuss outloud, they can often hear their own errors.

Each pair was given the same amount of plasticine.  That's an important bit for scientific study: only one thing should ever change in an experiment.

The designs were very different!

Every one of the above designs sunk!  Do you know why?  The students were given a second chance to modify their original design, and then they tried again.

What did we learn in the end?  If the plasticine is thin and the edges are up, the ship would float.  This was then related to the cargo ships.  The weight of the metal ships is distributed over a large surface area allowing a heavy metal ship to hold a cargo and still float!

Sailing, sailing.....or maybe not!

Since I don't have a magic school bus like Ms. Frizzel, our class has to rely on models during science class.  Today, a cork, a toothpick and a triangular shaped piece of construction paper became a model of a sailboat that I wanted to use wind power to get across the lake (the bucket of water).  The problem was that it kept falling over, making the sail wet.  What could we do to solve this problem?

After talking to their elbow partners, the students shared some of the ideas that they thought of or heard. One child suggested using plasticine to put two corks together.  It didn't work.

Another put many corks around, but the teacher said that it broke the rules, because the single centre cork was the sailboat, and you couldn't add 6 smaller boats around it to keep it upright.

A little bit of plasticine around the bottom, almost worked, but the sailboat really wasn't able to catch any wind in this tipped over condition.

Finally, after at least 6 more inventive suggestions, a small broken toothpick was added to the bottom of the cork, and a small round ball of plasticine was added onto the end.  Look at the result!  What did the plasticine represent?  What was it a model of?

Boats have keels.  A keel is usually fin shaped and a boat can have small keels or large keels.  They extend into the water under the boat to keep the boat from tipping over.  They keep the boat stable.

Dr. Seuss

Even though many of the literacy bags that the Gr. 2 students have taken home were based on the stories of Dr. Seuss, I decided that it would be fun to look at his stories a little more indepth.  The students learned that a biography is the story about someone's life.  They heard about what Dr. Seuss was like as a little boy and that he published 14 stories BEFORE he wrote "The Cat in the Hat."

Dr. Seuss bet his publisher that he could write a story that children would want to read, using only 50 words.  The name of the story was "Green Eggs and Ham."  The students tried to write new sentences using those same 50 words.

The students have written why they would or would not like the Cat in the Hat to visit them, compared cartoon versions of the stories to the actual books, listened to the stories on the Ipads and Ipods, tried to create their own tongue twisters, like those in "Fox in Sox", and learned the meaning of the word onomatopoeia!

Here's a wonderful example of our playing with words.  This young lady put a mocket in her pocket!

Buoyancy and Boats: Can you make it sink?

Students at this grade level understand the concept of sinking and floating.  What challenges them is the WHY...why does one thing sink and another thing float.  The students often attempt to make generalizations to assist them with answering the WHY.  Some say that it is WHAT the item is made of. The generalization may be that an item made of wood will float and an item made of metal will sink.  Some generalize that it is the WEIGHT of an object that allows it to float or sink, so a toothpick is light and floats, but a nail is heavy so it sinks.  The challenge in this lesson, was to make a plastic lid, which floats, SINK.

The students could choose from the items we have in our science kit, and hopefully use their knowledge from the previous science lessons, to assist them with making the lid sink.  The young man who put the plasticine on the bottom was SOOO surprised when the lid still floated!

Here's an example of a sunk lid....with plasticine and nails on the top!

The students have not yet figured out WHY large cargo ships, made of metal, with tons of cargo on them, can stay afloat.  It is through these experiments that we will be trying to figure that out.

Playing "Catch-up"!

I'm sorry that it has taken a while for me to return to sharing our learning with the parents through our blog.  Because of the revisioning meetings of last week and then the preparation for the sending home of the Evidence of Learning binders, classroom actions just haven't been recorded.

I thought you might like to see how the cross stitching with the Ukrainian Bilingual Creative Arts students went.  Once the little sampler was completed, I sewed it onto a felt mitten, which became the covers to our writing.  Grade Two students retold the folk tale, focusing on adding adjectives, and attempting to add conversation into a story properly.  There are SOOOO many rules to follow!  Grade Three students created their own original stories, using the basic premise of the Ukrainian folk tale.  They had to choose a setting, characters, a problem and then a solution!

We have been skipping in gym!  Spring must be right around the corner!  The students have been learning many 'tricks' and today they skipped with a partner.  Think of the co-ordination and co-operation that this takes!

In pairs, the students can work on skipping shoulder to shoulder OR face to face, or both partners facing in the same direction!  All are challenging!  I heard that the Easter Bunny might be bringing new skipping ropes in some of the baskets this year!

The new Grade Two science unit is called "Buoyancy and Boats."  The first experiment involved predicting which items would float and which would sink.  We had to agree on the definition of those words.  Once the predictions were complete, in small groups of 3, the students tried it out.  They were surprised to find out that an orange floated!  When attempting to explain why, many of the students used the typical thought that "heavy things sink."  In the next few experiments, we are going to dispel that thinking! (It is the same kind of incorrect thinking as we have winter because we are farther away from the sun....just not true!)  Ask questions and see if your little scientist can share their new learning with you.

Finally, for these last two weeks before Spring Break, we are looking at stories by Dr. Seuss.  We are learning about his life (and finding out that stories about real people are called biographies).  Today we tried to make up sentences using the 50 words that Dr. Seuss used to write the story "Green Eggs and Ham."  We have looked at "The Cat in the Hat" and made our own Thing 1 and Thing 2!  Thank you to all the families who shared their own books with us.  I was so impressed that one mommy sent in the book that she had had when she was a little girl!  The children are just "eating" these stories up!