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| Homemade catapult |
The other day I received a newsletter from
Home ScienceTools, a supplier of science materials for teachers, parents, and anyone who
wants to do science at home.
This
company was started in 1994 in the garage of a chemical engineer and his wife,
when they couldn’t find materials for their own children.
Their letter got me thinking about learning
science and the value of doing science at home with your children.
Science begins with questions and kids are natural
questioners. We all know that kids have
millions of questions and feeding that curiosity helps them build a lifelong
habit. The questions that they ask about
are the important ones to start with.
And the ones that come from their observations and interactions with the
world provide a natural entryway into hands-on science. Encouraging these questions and having the
tools nearby to explore their ideas, empowers them and removes it from the
realm of a homework assignment.
You learn science by doing science, by actively
investigating the world around you. Reading about science is wonderful and
rewarding.
For really learning how to do
science, however, nothing beats looking at a bug under a microscope, digging up
some compost and watching the critter, or mixing up cornstarch and water and
playing with it.
It is a
well-established principle that active involvements with real materials leads
to more and deeper learning that simply watching a demo, live or on
YouTube, or
just reading about it. See
How People Learn.
Nothing is wrong with reading science or
watching science shows; they are just not as effective as doing hands-on
science. Both definitely have a role, especially when they encourage kids to
try things out for themselves.
Learning science actively naturally leads to developing
skill in the inquiry process used by scientists. When children learn to form
their own questions and then to try things out, to experiment in order to
gather evidence, they are doing science.
They are doing science the way scientists do science. It is a short step to recording data,
interpreting that data, and sharing their discoveries with others.
Science is not about amassing facts; science is a process of
discovery that generates new knowledge. For
a child trying to make her baking soda and vinegar bottle rocket go higher, she
is discovering knowledge new to her that expands her world. If she is encouraged and supported, then
maybe one day, she may be at Stanford experimenting with a new idea in rocket
propulsion. She is now discovering
knowledge that is new to the entire world and that expand the possibilities for
all of us.
This activity is pretty
simple. All you need is a washed, empty
eggshell; some plain, white vinegar; a glass tumbler to hold the dissolving
shell, and a pie plate or other broad, flat dish for growing your crystals. I
took an eggshell from my breakfast, washed it out with water, and put it in an
old jelly glass. I broke mine into smaller pieces so it would react and
dissolve faster. Then I poured on enough plain white vinegar to cover it. Any vinegar should work, but plain vinegar
will make it easier to watch the reaction.
As soon as you pour the
vinegar over the eggshell, you’ll see carbon dioxide bubbles coming off the
shell as the acid reacts to the shell’s calcium carbonate. After a couple of
days, a white inner coating from the shell will slide off and you can discard
it. Let the shell sit in the vinegar for about 5-7 days until it is mostly
dissolved. Once you are down to just a few fragments, you then run it through a
fine kitchen strainer or even a coffee filter to take out those remaining bits
of shell. Pour the vinegar-calcium solution into a pie pan or some other
broad shallow dish so it will evaporate quickly. You’ll get better crystals
if you let it evaporate slowly. I put mine in a closet and left it for
another week or so until it is all evaporated. These are the crystals I
got in the photos.
