The Coral Christmas Tree
Deep underwater on tropical coral reefs, you might find a tiny, colorful forest of Christmas trees! These aren't actually trees, though—they are the "crowns" of the Christmas tree worm. Each worm has two beautiful, spiraling fans that look like pine branches, which they use to breathe and catch tiny bits of food floating by. If you try to touch one, it will zip back into its hole in the coral in a blink of an eye, only to peek back out again about a minute later when it feels safe! Learn more!
Wee Ones
A Christmas tree worm is shaped like a pointy cone. If you were a tiny fish looking straight down at the worm from above, would it look like a circle or a triangle?
Little Kids
A Christmas tree worm is 4 centimetres long. If he hides in his hole and only 1 centimetre is still sticking out, how many centimetres of his body are hidden inside the coral?
Big Kids
Each Christmas tree worm has 2 colorful fans. If you count 20 fans on a piece of coral, how many worms are there in total?
The Sky's the Limit
A group of 49 Christmas tree worms lives in a square patch of coral. If they are arranged in a perfect square with the same number of worms in each row and column, how many worms are in each row?