From Slime to Shine

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?

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.

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