A pearl is a beautiful, smooth ball from a weird place: the slimy inside of an oyster. If a scratchy grain of sand gets inside the oyster, the oyster smooths it by coating it with layers of “nacre,” or mother of pearl. The sand becomes a shiny little ball, and people make jewelry out of them. The world’s longest pearl necklace has 316,474 pearls and weighs almost 375 pounds. Very hard to wear!

*Wee ones:* What shape is a pearl? (The yellow arrow is pointing to a pearl in the picture!)

*Little kids:* If you hold 1 pearl on each tip of your fingers and thumbs, how many pearls do you have? *Bonus:* If you need 5 more to string them around your wrist, how many pearls will you need in total?

*Big kids:* If you added one more pearl to this 316,474-pearl necklace, how many would it have? See if you can remember the rest of the number! *Bonus:* If each pearl is about 1/2 inch wide, how long would a 30-pearl stretch be?

Answers:

*Wee ones:* A circle (its cross-section, looking from the side), or in 3D it’s a “sphere.”

*Little kids:* 10 pearls. *Bonus:* 15 pearls.

*Big kids:* 316,475 pearls. *Bonus:* 15 inches.