This year, my 6th grade students are using a monarch to practice the scientific method. Two of my own children volunteered to search through some milkweeds near our house so I would have a caterpillar for my classroom. (Note #1: The monarch will be released outdoors following our experiment.)
I started by showing the students a live monarch caterpillar that was placed in a jar with ventilation holes in the lid. (Note #2: The holes are punched from the inside of the lid with the sharp edges on the top of the jar lid. This allows for a smooth surface on the inside of the lid for the caterpillar, but the jar must be handled carefully to prevent injury. I placed red tape with the word SHARP on the top of the lid.) A stick and some milkweed were placed in the jar. A couple of the students could identify the caterpillar by its characteristic stripes. Others commented that it would become a butterfly. Some mentioned that it would make a chrysalis. Since my students understood that the caterpillar would go through steps to change into a butterfly, I was ready to continue.
Students got out their science notebooks and I introduced the problem we were attempting to solve: How many days will it take for the caterpillar to emerge from its chrysalis as a butterfly? As I mentioned in an earlier post, I always remind students that they are not allowed to share their hypotheses yet. I then asked the students to record their hypotheses in their notebooks by completing the following sentence: I think that the monarch will emerge from its chrysalis as a butterfly on Day # _____ because . . .
After I checked their notebooks, each student shared his/her hypothesis with the class and explained why they made that prediction. I love hearing my students’ ideas!! There was a wide range of guesses (12-64 days) since students were not sure how long the caterpillar had been in the larval stage, how big it would actually get before beginning to make the chrysalis, or how many days it needed to be in the chrysalis. Students then made Day 1 observations and recorded their findings in their notebooks. Observations are recorded daily until the butterfly emerges from the chrysalis.
This lab experiment can be differentiated for all ages and abilities. Watching a caterpillar become a butterfly is fascinating for students at any age and is an engaging way for students to practice using the scientific method to solve a problem.