You Will Need:
A small bag of pretzels, nuts, screws, nails, legos, etc.
Every family member guesses or estimates the quantity of the items in the bag. Then the bag is emptied out and the items counted. After counting, you can talk with your child whether there are more, less or the same amount as they estimated.
At first, your child may guess very high or very low estimates. However, with practice, their estimates are likely to get more realistic.