As students continue to work on developing their mathematical skills, they will need to learn how to estimate products when multiplying by 2-digit numbers. Estimating products is an essential skill that allows students to quickly calculate approximate answers to problems in math. Below are a few fun classroom activities that teachers can use to teach students how to estimate products when multiplying by 2-digit numbers.

**1. Estimating with Rounding Numbers:**

The teacher can start the activity by giving a 2-digit number to each student in the classroom. Each student then rounds off their number to the nearest ten. Next, students can pair up with a partner and multiply their rounded numbers. Ask the students to compare their estimate with the actual product and take note of the variances. The class can then discuss their results and take note of any patterns.

**2. Estimation Races:**

The teacher can place a multiplication problem (2-digit number multiplied by another 2-digit number) on the board. Then, the students can race each other to come up with the closest estimate to the actual product. The student who accurately estimates the solution in the fastest time wins the game.

**3. Paper Bag Estimations:**

Another fun activity for estimating products involves using paper bags. The teacher can fill a bag with small objects (such as marbles, beads, or candies) and have the students estimate how many items are inside. The class can then use multiplication to determine the total number of items in the bag. The teacher can then reveal the actual number of objects in the bag to compare with students’ estimates.

**4. Mind Games:**

In this activity, a 2-digit number is given to each student in the class, and a second number is then generated randomly by the teacher. Next, the students should then mentally multiply their number by the given random number. After multiplying, the students can compare their numbers to check who had the closest estimate.

**5. Fibonacci Estimation:**

Using the Fibonacci number sequence, students can estimate the product of 2-digit numbers. The Fibonacci sequence is a pattern of numbers where each number is the sum of the previous two numbers in the sequence (0, 1, 1, 2, 3, 5, 8, 13, 21, 34, etc.). Students can multiply the two last numbers of the Fibonacci sequence that come before the two-digit numbers to estimate their product.

In summary, these classroom activities provide a fun and engaging way for students to estimate products when multiplying by 2-digit numbers. Through these games, students can develop essential mathematical skills while improving their accuracy and speed in solving mathematical problems. Furthermore, these activities can help students develop critical thinking and problem-solving skills, making them more adept at tackling complex mathematical problems in the future.