Final answer:
The nurse should include the concept of volume in the teaching session when discussing the inability of toddlers to judge conservation related to mass. Using examples such as pouring liquid from one container to another can help illustrate this concept.
Step-by-step explanation:
The nurse should include the concept of volume in the teaching session when discussing the inability of toddler-age clients to judge conservation related to mass.
Volume refers to the amount of space occupied by an object or substance. It is important to explain to the parents that toddlers may not understand that even if the shape or size of an object changes, the amount of mass remains the same.
Using examples such as pouring liquid from one container to another with a different shape can help illustrate this concept.