Coral is made up of many polyps. The polyps are individual animals so when we want to make something to look like a coral we need to think about what can be used to show individual polyps.
An egg carton is a perfect recyclable candidate for becoming a coral colony because of all the individual holes the eggs sit in. We can turn it upside down to show closed polyps and we can cut some of the egg cups out and turn them right side up to show polyps that have opened up.
Because egg cartons are made from paper we can also utilise the excess material from the carton and use it like papier-mâché to further shape our coral colony.