Thanks so much for the ideas. In the end I went with our strengths and enlisted our resident Chemistry professor, so the lesson focussed on connecting the unique properties of water to various ways we can view baptism and the church community. This lesson may be a little science-heavy for some, but our kids all liked it, with our high school student even coming up with additional symbolism to connect some of the experiments to the story. Unfortunately, I forgot to write them down.
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