Gambling Mathematics with Coins

Have you played tic-tac-toe the Roman way? Open your wallets, shake out your piggy banks — you'll need coins for gambling math games!
Here are time-tested puzzles and experiments by Yakov Perelman, Emelyan Ignatiev, Mikhail Gershenzon, Tom Tit, and Martin Gardner — classic popularizers of science. These brain teasers are surely familiar to parents and grandparents, and now it's time for modern schoolchildren to get acquainted with them.
Coin games develop logic, spatial imagination, unconventional thinking, and creativity. Additionally, this fascinating journey into the world of mathematics will help instill in children a taste for genuine learning, teaching them to think rather than rote memorize or copy.
For middle school age children. For younger school children, collaborative work with adults is suggested.