Planning Your Own Investigations
scientists observe the natural world, they ask questions about things
that interest, surprise, or confuse them. Then they set up investigations
to try to answer their questions. As scientists participating in Journey
North's Tulip Experiment, you will surely wonder about many things — and
have a chance to explore them firsthand. Let's consider soil temperatures.
know a bit about soil. You've probably played in it. You certainly dug
into it when you planted your tulips. You may even be keeping track of
kinds of things do you wonder about soil temperatures? Here
are some of the things other Journey North students have wondered:
the underground temperature change during a 24-hour
the soil temperature higher or lower than air temperature?
it cold deeper in the ground?
does the soil still feel so cold?
sunshine change the soil temperature underground?
soil temperatures affect how fast tulips grow?
hot or cold is it a mile down? In the center of the
soil temperatures the same in different microclimates?
soil temperatures of bare ground and insulated ground
different? Does the amount of insulation matter?
at these questions (and your own). Put an E by
questions you can answer through observations or doing an experiment.
Put an L by those you'd have to answer by doing library
research or talking to an expert. Do the same with your own list.
a good question takes some thought
a "testable" question. Choose one of your questions
to explore. You may need to revise it so it's not too broad or
vague, and so it identifies the factor(s) you'll investigate. Here's
You wonder: Is it cold deeper
in the ground?
Testable version: How do soil temperatures
change with increasing soil depth?
As you plan
to carry out your investigation this spring, try to answer these questions
in your science journal:
Try a Hobo Data Logger.
Students can use it to measure and graph soil temperatures, moisture,
are we trying to find out?
do we already know or think you know?
the best way to answer our question?
variables/factors should we consider (e.g., soil temperature and
- How will
we keep it "fair"? (That is, keep everything the same except
the variable we're testing. In this case, soil depth.)
kind of data (e.g., observations or measurements) will we collect?
do we predict we'll find (or What's our hypothesis)?
evidence would support our predictions/hypothesis?
will we organize our data so we can make sense of it?
Science Education Standards
- Ask a
question about objects, organisms, events.
questions that can be answered through scientific investigations.
investigations involve asking and answering a question and comparing
that to what scientists already know about the world.