Thursday, August 16, 2012

9 Backyard Science Experiments

My children are educated in the public school system. However, I strongly believe that parents are a child's first and most important teacher. Over the years we have engaged in some after-schooling activities. And every summer, I pick certain themes for each week so that we can read books from the library and plan activities in a way that is exciting and educational.

So today, as I was trying to wrap up our recent science week lessons, I decided that we needed to do a little tree study. There are many transpiration experiments online and it seemed an easy enough subject to describe (my favorite online explanation is this one). So I headed out into the backyard with a bag and a rubber band, planning how I would explain to my "eager" children that trees breath and sweat.

I explained to my kids that trees breathe in carbon dioxide and breathe out oxygen. Lucky us, since we breathe in oxygen and out carbon dioxide. Trees also take in water and nutrients through their roots then "sweat" out water through the stoma on their leaves as a way of pulling water up through the tall plant. The water quickly evaporates off the leaves and into the atmosphere ... unless we catch it first. The plastic bag went onto the tree, covering a small bundle of low hanging leaves. The rubber band then went around the bag to secure it. We checked back often and found that the transpiration was slow at first, but really picked up once the leaves were in full sunlight. The warmth of the sun made more of the water condense on the inside of the bag explained my eight year old!

There are so many simple backyard experiments to keep us outdoors and learning in a natural environment. Try one today:

1. Solar energy experiment:
Place ice cubes on white and black paper, other colors as well, and compare melt rates.

2. Worm farms:
Fill a large clear container with dirt and several ants or worms. Watch as they tunnel through the dirt.

3. Feed some ants:
Ants stomachs are apparently transparent (I haven't tried this one yet. But it looks really cool!).

4. Build a moisture trap:
Learn about how moisture condenses in the cool air of the night by catching the dew for morning observation. Dig a hole and place a small plastic container in the bottom. Cover the hole with plastic wrap and secure the sides with stones. Place a few small pebbles in the center of the plastic causing it to sag but not collapse. Check back in the morning.

5. Make a compass:
Check out a map, consult your iPhone compass, or build your own with household materials.

6. Make a weather station:
Measure the temperature with an outside thermometer. Plant pinwheels in the garden to measure wind speeds - fast or slow. And make a rain gauge out of an old plastic cup to catch and measure precipitation.

7. Look for fossils:
With a magnifying glass in hand, explore backyard rocks or shells looking for regular patterns or swirls.

8. Watch seeds grow:
Plant seeds in small compostable containers such as toilet paper rolls, eggs cartons, or tea bags. Keep the seeds wet with a spray bottle, observing the plants growth each day. After about 2 weeks, transplant the entire container into garden soil.

We'll continue to collect great ideas for learning in the backyard on our Classroom Without Walls Pinterest board. Leave a comment below with your favorite backyard science experiments and we'll pin it!


  1. lots of fantastic ideas there! We love garden science.

    Have you seen our transpiration flowers?

    Thanks for linking up to Science Sparks xx

    1. We've done something similar to the transpiration flowers here:
      but we may have to revisit this experiment now that we've seen why the color moves up the stem of the flower. And then some strawberry milk shakes to further illustrate the point!

  2. Great list of experiments - and I love the tree one you did!