The Lost Isle of Change

You and your classmates have been mysteriously shipwrecked on the Lost Isle of Change. On your initial search of the island you discovered 7 hexagonal shaped stone tablets that you believe will help you signal passing ships and get rescued from the island.

Use your cunning thinking skills and knowledge of chemical and physical changes to decipher each stone tablet and unlock its hidden code. Work fast! You do not have much time before the last ship passes the island and all hope for rescue will be lost. Good luck!