Due Date Countdown Jar Guess

Set out a jar, slips of paper, and pens near a visible calendar.

Each guest writes their guess for the baby's actual arrival date on a slip and drops it in the jar.

Seal the jar and set it aside until after the baby is born.

Once the baby arrives, the host opens the jar and checks the guesses against the real date.

The guest with the closest guess wins a prize mailed or delivered after the birth.