There is a rumour that you can only balance an egg on either the spring or autumn equinox. To test this theory, perform two class demonstrations, first on the day of the equinox and again a few days later. Ask students to complete a standard science experiment prediction, getting group consensus on the hypothesis. Search online for a simple scientific method worksheet for them to use.
Complete the first demonstration. Were we successful? Discuss.
After a few days, repeat the experiment. Was there success? What did this prove? (Eggs can actually be balanced on a hard surface on any day, not just on the equinox)
To see how it’s done and learn the background behind the rumour, check out this article on National Geographic Kids. For more experimenting, try the ideas in “3 Ways to Balance an Egg” on Wikihow.