According to Piaget’s theory, which activity best supports the development of…

Concept — Conservation is the understanding that a quantity remains unchanged when only its appearance or arrangement changes.

In the concrete operational stage, children strengthen this idea through hands-on comparison and reversibility, rather than through verbal recall alone.

Application — When the same water is poured into a container of a different shape, its height or width changes while the amount of water remains constant. Comparing the two appearances and mentally reversing the pour directly engages conservation of liquid quantity.

Contrast

• Counting pencils practices one-to-one correspondence and cardinality in a discrete set; conservation of number would additionally require checking whether the count stays unchanged after rearrangement.

• Reciting a unit definition practices verbal knowledge about measurement but does not transform the appearance of a fixed quantity.

• Drawing a line practices spatial representation and fine-motor control rather than comparison of the same liquid under a transformation.

Cross-check — If the same water is poured back into the original container, its earlier appearance returns without any change in quantity; this reversibility checks the conservation reasoning.

Result — Therefore, pouring water from one container to another of a different shape is the activity that most directly supports conservation of liquid quantity.