When finished with the activity, ask students to discuss the question with a neighbor before writing creatively about a philosophical paradox.
"The Ship of Theseus" is a true classic when it comes to thought experiments, but the concepts are easy to grasp by even very young students. A much simpler version is "Grandfather's Axe": if you change the handle of an heirloom axe, and then the head, is it still the same axe your grandfather used?
A very readable discussion you can review to prepare yourself for a philosophical discussion about change and identity appeared in the pages of the Utne Reader:
The premise stated in the introduction to the Utne article is largely refuted by this video, made by SciShow.
This video "Your Body's Real Age" by Skunk Bear, a video producer for National Public Radio (NPR), looks at the lifespan for different kinds of cells of the human body: youtu.be/Nwfg157hejM
For the first slide, paraphrase:
We've talked about transplanting organs to save lives. Our bodies are changing all the time, making trillions of tiny transplants at a cellular level as cells die and get replaced by copies of themselves.
For the second slide, paraphrase:
Think about a ship that is fixed over decades: planks rot and get replaced, the sail gets holes. In the end, no part of the ship is the same as it was when it was first built. Is it the same ship?