1. Investigation #1: What makes worms happy?

2. There are approximately 2,700 different kinds of earthworms.
Worms live where there is food, moisture, oxygen and a favorable temperature. If they don’t have these things, they go somewhere else.
In one acre of land, there can be more than a million earthworms.
Worms tunnel deeply in the soil and bring subsoil closer to the surface mixing it with the topsoil. Slime, a secretion of earthworms, contains nitrogen. Nitrogen is an important nutrient for plants. The sticky slime helps to hold clusters of soil particles together in formations called aggregates.

3. Today’s essential question …
Investigation #1:
What makes worms happy?

4. Team Roles Data Recorder
Experimental design artist / sources of error detector
Time keeper and reporter
Worm handler & materials specialist / safety officer

5. Brainstorm
So what does make earthworms happy? Create a list of four things with the reasons you think these things would make the worms happy.

6. The experimental design – Choice Chambers
How many things should we test at the same time?
What data will you collect and how will you do it?

7. Independent variable – the thing that is tested.
What is your independent variable?
How will you know if you’ve observed a change to you independent variable?

8. Dependent variable – the observed change.
What do you predict will happen based on the independent variable that you have selected?
Are there things we should all be doing in the same way?

9. Control – the variables or conditions we all keep the same.
What should we all keep the same?

10. Run the experiment – collect data
Collect data on the location of your worms every minute for ten minutes. Record the data in your table.

11. An unhatched earthworm in it’s cocoon.
Now switch tables and repeat another teams experiment. Use their worms and materials Did you get the same results?
An unhatched earthworm in it’s cocoon.

12. Teams meet and Report findings
How were your tests the same or different?
What were possible sources of error in the experimental design?
Was your initial hypothesis supported by your findings?
Want to know more about this giant earthworm?