Sink or Float

This is a popular science experiment for kindergarten children. I have done this experiment 3 times, here is a write-up of each activity. I have to mention that these activities have integrated the different domains required by NEL. There is no need to make time for "English" or "Math" lesson.

Activity #1:
.Group children into 4 groups to try the next science experiment. The following are suggested instructions, children only have to ensure area is clean.
.Introduce the following materials: salt, baking soda, stones, 1 marker, 3 containers each group.
.Talk about the activity, and children have to gather hypotheses on which ingredient will cause the manipulatives to sink or float.
.Distribute worksheets with 2 sections. Instruct each group to do 1 worksheet, and to do their hypotheses on the top, the findings at the bottom.
.Get children to pour the ingredients into the 2 containers, 1 container will be empty.
.Pour water equally into the 3 containers, get them to tell the teacher to stop when water level is reached.
.Instruct them to label the containers as such: Salt, Baking Soda, Water
.Give them some time to explore the containers by dropping the manipulatives into the containers.
.Allow free-play, but only introduce the materials for them to use. Allow them to use anything in class, but put them back.
.Summarise the activity by getting children to share their findings, and compare with their hypotheses.

If you want to download the PDF of the worksheet, click here.

Activity #2:
.Introduce the materials used: milk, soap bubbles, coloured water, 3 containers to hold the liquids, 1 transparent cup for them to pour inside, 1 container of random objects, 1 dropper
.Get each group to come to the teacher to collect the containers of liquids and materials, while the rest will wait.
.Encourage them to make their own hypotheses again for this experiment, then test them out by trying.
.Inform them to use the dropper to add in the liquid, so they don't mix together. Then they can add in the small objects to see whether they sink or float.
.Summarise the activity to talk about density.

Activity #3:
.Divide children into groups.
.Distribute materials (that can either sink or float on water) for children, get each group to build a mini boat on their own using the materials. They are allowed to use anything else, but they must ask permission.
.Inform them the boat has to stay together and floating on the water.
.Show each boat, ellicit hypothesis from the children on whether each will float or sink.
.Bring each boat to the container of water near the garden to test out, place them one by one gently on the water, to test the hypothesis.
.Mention the boat must float for 10 seconds to succeed. Get them to redo when unsuccessful.
.Summarise the activity, get children to share their honest reflections. Talk about what makes their boat float. (E.g. Using light materials)
.Ellicit curiosity, ask them how a heavy ship floats on water.
.Talk about principle of buoyancy.
.Link to the heavy aeroplane able to fly in the sky.
.Get them to try the experiment with an orange, unpeeled then peeled at home. Get them to share their findings the next day.

(The next day)

.Talk about the Science experiment they conducted at home the previous day, get them to share with their friends on their hypothesis and findings.

.Get them to share about what they did at home, for them to remember what they did. (Nobody tried the experiment at home)

.Link to the principle of buoyancy, of the ship.

.Mention that heavy objects will sink in water, but when placed in an object that has buoyancy it will float.

.Demonstrate the orange science experiment with them, talk about how the skin gives buoyancy but the orange will sink in water.