Nature Study Lesson 107: Invertebrates: Earthworms
When we studied snakes, I had forgotten to do an activity called “Slithering Like a Snake.” It's purpose is to teach that snakes move in one of four ways...
1. Lateral undulation – sideways waves
2. Rectilineary – straight line
3. Concertina – Coiling
4. Side winding – Angled
After telling them this, I had them try to move like a snake on the floor and then the rest of us guessed which of the four movements they made.
Next we moved on to earthworms. My plan was to dig up some earthworms and to then get some "red wiggler" worms from Katie's composter and compare and contrast the two. 
But digging where earthworms had been spotted in the past did not prove successful, so we had to complete our nature study with Katie's worms. 
We chose not to make a wormery in a jar, because the boys were familiar with Katie's wormery.
We put our worms on a wet paper towel so they would not dry out as they need to be wet in order to breathe. Worms do not have lungs, but take in oxygen through the skin and this process needs the skin to stay wet.
But digging where earthworms had been spotted in the past did not prove successful, so we had to complete our nature study with Katie's worms. We chose not to make a wormery in a jar, because the boys were familiar with Katie's wormery.
We put our worms on a wet paper towel so they would not dry out as they need to be wet in order to breathe. Worms do not have lungs, but take in oxygen through the skin and this process needs the skin to stay wet.
We first looked at how they move, to compare them to the snake. Whereas the snake uses it's muscles and scales to move, the worm uses its muscles by squeezing them in and out and uses bristles on its underside called setae.
Worms have both circular muscles, which tighten to make their body thinner and longer, and long muscles which squeeze together to move the rear end of its body towards the front end.
We looked at the rings around their bodies, called segments and looked for the a lighter colored section, which is the clitellum. Since the clitellum in near the front end of the worm, finding the clitellum helps to determine which where the ends of the worm are. This was not as easy to see on the red wigglers as it is on earthworms.
Once the front end is found, you can look for the mouth.
Once the front end is found, you can look for the mouth.
Looking through a magnifying glass one can see a flap of skin that hangs over the mouth. It is called the prostomium, which keeps stuff the worm doesn't like from getting into its mouth. Right under the prostomium is the mouth which is big enough to grab a leaf and drag it into the worm's tunnel. 
Once the boys had made their explorations, they began drawing their nature journal pages.
Nature journals are encouraged but not required, so they keep them as they wish. They included in their drawings the aspect of the color and length of their worms.
Student (fourth) was just a sketch of his worm. 
One student (fifth) wanted to draw about all the things he had learned but needed me to write down the words. I wrote while he narrated what he remembered. He wanted me to put in the correct terms (setae, clitellum) even though he did not remember those.
Once the boys had made their explorations, they began drawing their nature journal pages.Nature journals are encouraged but not required, so they keep them as they wish. They included in their drawings the aspect of the color and length of their worms.
Student (fourth) was just a sketch of his worm. One student (fifth) wanted to draw about all the things he had learned but needed me to write down the words. I wrote while he narrated what he remembered. He wanted me to put in the correct terms (setae, clitellum) even though he did not remember those.Another student (third) sketched and wrote about what he observed.
