Fifth Grade Soil Comparison Experiment
Objective: To allow students to see how different types of soil and water interact and discuss how the
water/soil relationship affects farming and gardening practices.
Materials needed: Samples of sandy, clay and amended soils; plastic cups, coffee filters, rubber bands
and containers for water; worksheet for students to complete; shovels and compost to be put into
garden beds.
1. Discuss the different types of soil – sandy, clay, silt and combination of these. Different types of
soil interact differently with water. You will get to do an experiment to see how 3 different
types of soil interact with water.
2. Review the worksheet with students explaining the experiment. Divide class into 3 groups.
Two groups observe soil samples and 1 group goes to garden to remove weeds and add
amendment to soil. When first group is done outside, they will observe soil, 1 group who had
been observing soil will do experiment and 1 group will go outside. Then rotate again.
3. After all groups have done all three stations, hold group discussion. What were your
observations about the different types of soil? Which soil sample was sandy, clay and amended?
Which allowed the water to go through the most quickly, second, least? Did this match what you
hypothesized?
4. How does knowing what type of soil you have affect what you need to do when farming or
gardening? Explain that all the soil samples are from gardens where I have gardened. The
sandy soil is from Sunnyside, Washington. Water goes through it very quickly and few of the
sandy particles got through the coffee filter. Why is that? This type of soil has to be watered
longer to saturate the soil and make sure the roots can get water. Removing weeds from this
type of soil is easier than from the clay soil and the roots come out without much soil stuck to
them. The clay soil is from Draper, Utah. I grew up gardening here and it was more difficult to
pull weeds. They come up with clods of dirt hooked on them. The clay soil clods a lot more than
the sandy soil. It also holds the water much longer and took the most time for the water to get
through. What did the water look like and why? (Dirty because the clay particles are much
smaller and can go through the coffee filter with the water.) May be more difficult for seeds to
grow unless soil is worked well to break up clods. The other kind of soil is from the Sharpstein
Garden. It has had amendments added so that the soil is not too sandy or clay like. The water
doesn’t go through as fast as the sand or as slowly as with the clay. Soil also doesn’t clod as
much as the clay soil.
5. Knowing the type of soil you are working with affects how much you need to water, what type
of amendments you need to add and how you need to work the soil when gardening.
Notes: I also brought some red soil from Southern Utah because it is pretty different in color. The
students were able to record observations about it but did not do the experiment with it. It is sandy and
acted similar to the other sandy soil when I experimented with it at home (I’ve also never gardened in it
so didn’t have personal experience to add about it). I did mention that the soil has iron in it that makes it
red. This lesson was kind of specific to what I’ve experienced in my gardening, but I’m pretty sure sandy
and clay type soils could be found if someone else wanted to repeat it.
The students helped a lot outside getting the garden cleaned up. I had a great volunteer who talked
about why the soil needs to be worked and why amendments are important to add in. For 2 of the
classes, the observation and experiment were done in the classroom and then one group just went out
to the garden at a time. For the last class, the whole class went outside and did the observation and
experiment on tables near the garden. It was fun to all be outside and the students kept their focus well
enough to get their worksheets done.