Tuesday, October 23, 2007

Sink and Float

The idea of sink and float is a very important lesson to teach to Kindergarten students. I incorporate a science experiment dealing with sink and float when I am teaching a thematic unit on pumpkins. The students are presented with various different items (wooden stick, cotton ball, crayon, pencil, paper clip, rubber band, and pumpkin) to test whether they sink or float (question). The students must first predict (guess) whether each item will sink or float. Each student is encouraged to pick what he/she thinks will happen and record it in their science journal. After each student has visually seen each item and decided whether he/she thinks it will sink or float, as a class we perform the science experiment.

Students are called up to be helpers and drop one of the items in the clear bucket of water. The first item is dropped in and then we observe what happens to it after fifteen seconds. Some of the items will immediately sink to the bottom, while others will float for a few seconds and then eventually sink. We discuss reasons why this happens (sink to float) including what each item is made of. The students are introduced to the vocabulary word "absorb," because they question what happened to the cotton ball. Students are also explained what the words "solid" and "hollow" mean.

After each item is dropped and observed, students record again in their science journals what actually happened when the experiment was performed. We continue to discuss other items that will either sink or float when dropped in water (including ourselves). We also discuss why it is important to conduct the experiment several times to make sure that we observe the same outcomes each time. The students now understand the idea of sink and float so I add it to the science center to further enhance their learning!

Here are some ideas for how to incorporate technology into this lesson:

1) Students can play the sink or float game on the Nickelodeon website (Blue's Clues) at the computer center.

2) This is another website that has a great game that students can play in the computer center to continue exploring what things sink or float.

3) This is a website that I share with my parents on ideas that they can use at home to increase their child's understanding of science, including sink and float.