The preschool science experiment is an opportunity to introduce kids
to the concepts of observation, prediction, and testing (Gelman and
Brenneman 2004). Exciting? Yes. But it's also tricky.
Research suggests that young children don't think as creatively or critically when adults tell them what to do. Simple instructions, like, "It works this way..." appear to deter kids from investigating and testing ideas of their own (Bonawitz et al 2011; Buchsbaum et al 2011). It's as if kids assume the adults have told them everything they need to know. All that is left is to carry out the procedures, faithfully and uncritically, whether or not they seem to make sense.
So when we give kids the chance to experiment, it's important to avoid lectures or the appearance that we have all the right answers. Children need time to investigate things on their own and generate their own questions.
Here I present an example of how adults can foster scientific exploration without getting in the way of kids' need to think for themselves. The activities introduce the scientific method and to present kids with the idea that matter can
Water can be a liquid and a solid. What conditions transform ice into water?
Starting at the beginning: Explorations of ice
Before kids can test their ideas about ice, they need time
develop their ideas. So start with an unstructured activity: Give
children a plastic bowl of ice cubes and let them play. You can play,
participate as a peer, not a teacher. The goal is to let kids make their
own discoveries. Kids might try the following:
• “Painting" (i.e., drawing ice cubes across different surfaces to see what tracks they leave behind)
Questions to ask
• What makes ice melt?
• What eventually happens to your ice "paintings"?
If you like, you can also encourage kids to record their observations (by drawing or having you take dictation) in a notebook.
These experiments introduce kids to the idea of making
predictions--i.e., thoughtful guesswork about the outcome of an
They also present kids with the concept of contrasting two
different conditions (e.g., warm water v. cold water).
Experiments #1 and #3 can be performed indoors.
Experiment #2 should be performed outside on a sunny
day. The hotter the better, but you will need a source of shade!
Preschool science experiment #1: The effects of warm water on ice
• Ice cubes
• Two bowls
• Cold and warm water
Provide kids with two bowls of water—one very warm (but not
scalding), the other very cold. Let kids make observations about the
temperature of the water (by testing it with their fingers). Then have
them consider what will happen if you put an ice cube in each bowl.
Ask kids to make a guess. Which cube will melt faster? Why?
Watch the ice cubes closely and discuss outcomes.
Preschool science experiment #2: Sun versus shade
• ice cubes
• sunny and shady surfaces
Before beginning the experiment, start a discussion about what makes
ice melt. Ask kids to make a guess: Where do you think ice will melt
faster? In the sun, or in the shade?
Have kids to put one ice cube in the sun and the other in shade. Watch and note the results.
Why did the ice left in the sun melt faster? Ask kids to stand in the
sun and then stand in the shade. Can they feel the difference?
Preschool science experiment #3: Ice and more ice...
• ice cubes
• two large bowls
• two small paper cups
Put an ice cube in each paper cup. Then, in the first bowl, place 1
or 2 ice cubes. In the second bowl, place many ice cubes (10 or more).
In this experiment, kids will place each cup (containing an ice cube) in a bowl. Ask kids to consider what will happen.
In which of the cups will the ice cube melt faster? The bowl with only a couple of cubes? Or the bowl that is packed with cubes?
Place each paper cup in a bowl. Make sure that the cups are standing
upright (so they don’t spill their contents). And make sure that the
paper cup in the bowl full of ice is surrounded by ice cubes. Watch and
note the results.
Why did the ice cube in the packed bowl melt more slowly?