Monarchs change throughout the life cycle. The phenomenon of metamorphosis, in which the caterpillar transforms into a butterfly, is readily observed. However, there are more minute transitions that are only visible through diligent observation. It is challenging to focus children's attention on the minute changes a caterpillar experiences. The coloring of the caterpillar changes, particularly the patterns of the black, white, and yellow bands. Students form conjectures about how the increase in food consumption leads to an increase in caterpillar length. Through regular and careful observation, students become more aware of the subtle changes in the growing caterpillar.

Children tend to anthropomorphize the growth of the caterpillar because they can relate it to their own growth experiences. This affords the children more ability to talk about the growth of the caterpillar. For example, the children related caterpillar digestion to human digestion, thinking the leaves were dissolved in the caterpillar's stomach by acids.

<Video for first Digestion Analogy>

<Video for second Digestion Analogy>

Children also were able to think about the digestion issue deeper through the use of agency, where they imagine themselves as being the actual milkweed leaf the caterpillar consumes.

<Video on Agency>

Although the children's ideas may be scientifically incorrect these clips emphasize the possible range of thinking about the concept of change.