Compound interest pays on the interest already added, so growth speeds up.
Ana and Sam each planted 100 pretend coins. Sam's Flat Patch adds ten coins every year, the same each time.
Ana's Snowball Garden adds one coin for every ten inside, and counts the new coins too. Interest earns interest, so growth speeds up.
At first the snowball is small and slow, but later it races.
These are some of the questions on the sets. The printable sheets have more and an answer key.
13 coins. 133 holds thirteen tens.
The Snowball Garden. Interest on interest is compounding.
150 coins. 100 + 5 × 10 = 150.
Ana, by 56 coins. 256 − 200 = 56.
With a grown-up, find something that grows faster as it gets bigger, like a snowball, a plant or a pile of folded paper. Talk about why.
Look for something at home that grows faster as it gets bigger, like a plant or a pile of folded paper, and talk about why. The gardens are made up and nothing real is promised: this is about how the idea works, not about what to do with money.
