Teachers TryScience

This activity can be conducted as either structured or open-ended design. For a more structured lesson, give specific instruction of the amounts of food you would like the students to use, and allow them to weigh it out themselves. Otherwise, you can provide students with a variety of compostable materials and allow them to predict what the worms would like to eat, and then allow them to determine the ratio of food to the number of worms themselves.

PREPARATION

1. Be sure to be familiar with composting on your own before doing this with students. Worms are live creatures, so part of the lesson and/or unit should be promoting the compassionate treatment of the worms. Doing the activity in the Spring might be a good idea, so that at the conclusion of your worm activities, you can release the worms back to nature if you choose not to continue composting yourself.
2. Before beginning this activity, you may want to view the video “Wormania!” by Mary Appelhof, which provides you with a practical how-to demonstration. Plus, it has cute songs written and performed by “Billy B.” YouTube also has many people who have posted their versions of composting (free!). You can also purchase Mary Appelhof’s video here: http://www.amazon.com/Wormania-Mary-Appelhof/dp/0977804534/ref=sr_1_1?ie=UTF8&qid=1321115718&sr=8-1
3. Gather materials and copies of any worksheets. The worksheets provided here are merely suggestions.

WITH THE STUDENTS

Part 1: Class Discussion

1. Begin a class discussion about composting. Possible questions may be: What is composting? Have you heard of it before and where have you heard it? Why is composting important in today’s world? You may want to view the Asking Good Questions video for more information.

Asking Good Questions Video

Part 2: Calculating the Amount of (and Selecting) WORM FOOD!

1. Give each group a copy of the Worm Food Calculations Worksheet.

   Worm Food Calculations Worksheet (PDF)

   
   

2. Divide the class into teams of two to four students each. Have the students predict the foods that they think that the worms would like to eat. Each worm bin will be split into four quadrants, so students should select four different food items and then make observations about which foods the worms seem to prefer.
3. Have students calculate the amount of food that the worms will be able to eat. To do this, they would weigh the worms that they will use in their worm bins. Take that weight and multiply it by 2. Worms can eat double their weight each day, so if you are only planning on “feeding” them 1 time each week, you would want to multiply that number by 7.
4. Divide the amount calculated by four. This represents the amount of food that will be buried in each quadrant of the worm bin.
5. Having selected four foods, have the students weigh each food using the above calculations. (Each food will represent ¼ of the amount of food that the worms are able to eat. Each one of the four food choices will be buried in their own quadrant of the worm bin.)
6. Have students record their calculations.

Part 3: Setting Up Your Worm Bins

1. Have students decide on a name for their worm bin (and worms!).
2. Have students review the Steps to a Worm Bin Worksheet.
   

   Steps to a Worm Bin Worksheet (PDF)

   
   

3. Instruct the students to shred their newspaper into very thin strips with their scissors. They will need enough to fill their bin half way.
4. Students should then dampen the newspaper to make it a good habitat for the worms. The key word is “dampen”; too much water and the worms will drown!
5. You can add a little soil or peat moss as well, but this is not necessary.
6. Add worms!

Part 4: LUNCHTIME! Adding Food

1. Divide the box into four quadrants on the lid. Label the quadrants so that the students will remember what is there. Students may use the Worm Bin Quadrants Worksheet to guide them.

   Worm Bin Quadrants Worksheet (PDF)

   
   

2. Bury the food in the four corners of the box.

Part 5: Observing the WORMS!

1. Instruct students to sit together with the members of their group and their worm bin.
2. Have the students remove the lids of their bins; remind them to be mindful of how they place the lids on their desks. They need to remember what food is in what quadrant, so if they randomly place the lid on their desk, they won’t remember what food is where. This would impact the observations that they make.
3. You may want to provide the Worm Bin Record sheet or the Worm Observation Chart to help your students keep track of their data.
   

   Worm Observation Chart (PDF)

   

Daily Observation: Have students look inside their bin to see what “activity” has taken place. They should record these observations in a journal or on the provided worksheet. Questions for discussion: Have the worms begun to eat? Is there one or more quadrant that seems to have a large number of worms? Students will need to assess their bin’s activity to determine if they need to add more food. Ideally, the goal should be to observe the worms daily (for five minutes) and then add food only once per week (full class period).

***Part of the daily observation is to check the level of moisture inside your bin. If the newspaper has begun to dry out, remind the students to dampen the shreds. Failure to do this will result in dead worms. They need moisture to live and to move throughout the bin. This should be part of an initial discussion on worm bin composting and when talking about worms and their habitats.

Weekly Observation: Have the students remove the food from each quadrant and weigh it. They should then compare the current weight of each food to its starting weight. Record the data on the provided worksheet. Questions: Did the worms seem to prefer one food over the others? Or did they eat everything? What do your observations tell you? How do you think you should proceed? Do you want to use the same foods, or do you think you need to change one or more foods?

Final Observation: Do the same as the above, but students should also determine the level of success they are having with their worms. Questions: How do you know that you have a healthy worm bin? What are the goals that a person should have when establishing and maintaining a worm bin? What have you learned? Would you choose to keep a worm bin at home and compost on your own if you were allowed to? Why or why not?