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 change states.
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, too, but participate as a peer, not a teacher. The goal is to let kids make their own discoveries. Kids might try the following:
Questions to ask
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 experiment.
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!
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.
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?
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?
For more activities and for tips about teaching science to young children, see my page on preschool science. In addition, check out this preschool science experiment about making mud bricks.
Bonawitz E, Shafto P, Gweon H, Goodman ND, Spelke E, and Schulz L. 2011. The double-edged sword of pedagogy: Instruction limits spontaneous exploration and discovery. Cognition. 120(3):322-30.
Buchsbaum D, Gopnik A, Griffiths TL, and Shafto P. 2011. Children’s imitation of causal action sequences is influenced by statistical and pedagogical evidence. Cognition. 120(3):331-40
Gelman R and Brenneman K. 2004. Science learning pathways for young children. Early Childhood Research Quarterly 19:150-158.
Content last modified 1/14
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