Floating+Egg+Lesson-+Buoyancy

**First Grade** **__Materials:__** Fresh water and salt water Science journal Containers Measuring spoons Spoons Small wood block Large marble Egg Small potato Carrot Chart Paper
 * __Floating Egg Lesson__**

**__Objectives__**: The students will be able to…. -Describe the effect of fresh water and salt water on the buoyancy of objects -Record in writing or tell the effect of fresh water and salt water on the buoyancy of objects -Compare and contrast the effect of fresh water and salt water on the buoyancy of objects -Give an oral definition of buoyancy

**__Background Information:__** Salt water is heavier than fresh water resulting in objects floating more readily in it. Salt water supports more weight and allows things to float more easily than fresh water.

(Please note this experiment needs a little more than 1 tablespoon of salt per cup of water to make the egg and carrot float. It will take 1 ½- 2 tablespoons of salt per cup of water to make the potato float.)

**Buoyancy**: the ability of water to support weight and the degree to which it can support that weight.

**Preparation:** Gather materials Copy science journal Put 3-4 cups of water in each of the two clear containers, labeled as salt and fresh water. Gather objects to test buoyancy

**Procedure**: __Activate Prior Knowledge__ Do you go swimming? Do you wear life jackets or use flotation devices? Can anyone float or swim without any of these devices? Where do you swim? Did you notice a difference in the ease of swimming in salt water? What’s the taste of salt water?

**Group Activity:** Teacher shows whole group two clear containers with water in them. Add salt to one container. Explain that the class is going to observe what happens when various objects are placed in each container. If the object sinks, it will be put in a pile and then recorded on chart paper graph. If it floats, it will be placed in another pile.


 * 1) Drop an object in container 1 (fresh). What did it do?
 * 2) Drop an object in container 2 (salt). What did it do?
 * 3) Does it go in the sink or float pile?
 * 4) Continue same procedure with objects.
 * 5) Complete chart together recording which items float or sink.

**Small Group activity:** At table groups students will test other objects in fresh water to determine if they float or sink. Students will record predictions and findings for each item in their science journal.

Students continue the same procedure but in salt water to determine if the objects float or sink. They will record predictions and findings for each item in their science journals.

**Individual Activity:** Students will place an egg in their cup of water. They will add salt, one tablespoon at a time, stirring after each spoonful. They will count how many spoons of salt it takes to make the egg float.

When the egg finally floats, student will record how many spoons of salt in their science journal.

**Discussion:** Discuss the results of these experiments. Which objects floated in fresh water? Which objects floated in salt water? Why did more objects float in the salt water? Were there any objects that did not float in salt water? Why?

Explain that we have recorded the results of the experiments. Ask do all of our recording have the same answers? Why would this be?

**Follow Up:** Remind students about the earlier discussion about swimming. Would it be easier to float in a swimming pool or the ocean? Why would this be? Discuss what buoyancy means and record in science journals.