Don't Worm Your Way Out of This One! Lesson Plan

• Review Related Resources and select a book or website to introduce the activity.
• Decide how/if you want to utilize parent helpers.
• Download a copy of Worms (sung by Peggy Eyres) with lyrics so you can sing it with your students, or check out one of the other worm songs listed in Related Resources.
• Gather the following materials:
  • vermicompost bin (worm bin)
  • Cheerios (or equivalent cereal)
  • napkins
  • spray bottle
  • samples of castings in small sandwich bags

• Group students into pairs at seats or on the floor.
• Have a parent or student helper pass out one napkin for every two students.
• Have a parent or student helper pass out one Cheerio for each napkin.
• Wet each napkin with one squirt using the sprayer bottle.

• Place a worm on each napkin and allow 5-10 minutes for student observations.

• Ask students to raise their hands if the worms on their napkins completely ate the Cheerio (no Cheerios were eaten).
• Introduce the word food chain--a way to show how living things get their food energy.
• Draw the following food chain--Cheerio >> bacteria >> worms
• Explain to students that it takes another living thing (bacteria) in order for the Cheerio to be eaten by the worm.
  Note: Before you or your students say (or think) "Gross!" keep in mind that our own digestive systems would not function without the aid of helpful bacteria.
• Make a new bar graph to predict how long it will take before the Cheerios are eaten in the worm bin.
  Note: One way to make a bar graph that can be modified over the week or so it will take for the Cheerios to be consumed is to have each student represent their prediction on a Post-It Note that can be moved each day (before or after observing the progress of the Cheerios).

A Little Bit More...

• Return students to their partner groups.
• Distribute a small amount of castings to each group in a ZipLoc sandwich bag
• Ask students to make two observations and to think of one question to ask about this "mystery soil".
• Collect castings.
• Discuss observations and questions.
• Ask students to make a hypothesis (a guess based on their observations) about how this soil was made.
• Explain that the soil is called "castings" and that castings are the rich soil made by worms when they eat food such as leaves, Cheerios, etc.

• Continue feeding and managing the worm bin in your room as a classroom center. Use Squirmy Worm Composters or another Related Resource for management suggestions. Most importantly, keep in mind the following:

  • Always bury food waste under the soil (except during the Cheerios investigation!). Note: Paper products are also food for worms. Paper can be mixed into the soil or used as a covering to help keep the soil moist.
  • Wormbins are very low maintenance. A well-fed, appropriately moist wormbin can be ignored for a month without any care or maintenance.
  • Don't over-feed. If you can't feed your wormbin without uncovering food, stop feeding it until you can.

  • Don't over-water. A worm bin should be as moist as a wrung-out sponge. When in doubt, drier is better.

• Harvest your worm castings! After 2-3 months, the food added to the wormbin will become rich vermicompost (worm castings).
  • What is vermicompost? Vermicompost (also known as castings) is a rich soil made by consumers such as worms, fungi, bacteria, pillbugs, etc. This rich soil is completely organic. The soil particles are so rich they must be mixed with lower quality soil or they will overpower plants.
  • Where did this vermicompost come from? These castings were originally paper plates, napkins, french fries, vegetables, bread, or other food waste you've put into your bin. Over a period of about two months, this waste was vermicomposted into the castings you see now.
  • What can I do with vermicompost?
    • Topping: Sprinkle a layer of organic compost (castings) onto the soil surface of household plants instead of using plant spikes or chemical plant food. Normal watering will mix nutrients into existing soil for the plant to use.
    • Potting/Repotting: Use a mixture of 1/3 vermicompost and 2/3 other soil(s). Mix soil together before potting/repotting.
    • Gardening: Mix 1/3 vermicompost with 2/3 regular soil when planting to give your garden the needed nutrients for a successful crop. Topcoat once or twice a month as needed.