A choice chamber for an earthworm can be used to observe their preference in different soil. This is mainly used for science experiments and observations. Buying a choice chamber specifically for this task can be pricey. However, a choice chamber for an earthworm can be made from home with a few simple materials and ten minutes of spare time.
Wash the sectional plastic container with warm soapy water to remove any existing residue or debris from the container.
Allow the container to air dry.
Use the scissors to cut away a small part of each of the sectional dividers.
Keep the cut pieces of container; they can be used to close off sections of the container in order to control experiments.
Fill the sections with the desired choices for the earthworms to begin the observation.
Sectional plastic containers are readily available from speciality web sites.