Let's learn about the life cycle of a butterfly!
Stage One: Eggs
Stage Two: Larva/Caterpillar
Objective: Students will be able  to describe, through the use of models, that organisms have unique and diverse life cycles but all have in common birth, growth, reproduction, and death. Applicable Standard: NYSP12SLS Develop models to describe that organisms have unique and diverse life cycles but all have in common birth, growth, reproduction, and death. (3-LS1-1)
Stage Three: Pupa/Chrysalis
During this stage, the female adult butterfly will lay many eggs. The eggs will take 1-3 weeks to hatch. 
Stage Three Continued: Metamorphosis
During this stage the larva/caterpillar emerges from the egg and starts eating plants. The main job of the caterpillar is to eat (Remember the Very Hungry Caterpillar).
Stage Four: Adult Butterfly
The caterpillar creates a pupa or chrysalis around itself and stays inside for a few weeks.
This is the stage where the metamorphosis happens. During this metamorphosis, the caterpillar will be growing wings and longer legs inside the chrysalis.  
After a few weeks, the metamorphosis is complete and an adult butterfly emerges from the chrysalis. The major change is that the butterfly can fly. The butterfly is now ready to repeat the life cycle.