# Find the Area: Guest Blog Post from education.com

Introduce the concept of area to your third grader with this fun card game. You’ll show your child how to determine the area of any object and help him begin thinking in terms of units as you create shapes out of playing cards. Count the cards you use or try applying multiplication to find the total area. Once you’ve got the hang of the game, assign different values to the cards!

### What You Need:

• Deck of cards
• Several players

### What You Do:

1. Decide on the unit value of the cards. If you decide on the number 2, each card will amount to two units and players will have to keep this value in mind when calculating the area of the figure you’re building.
2. Have the players take turns placing one card at a time face down on a flat surface. Every card placed down should touch the side of another card. Cards should not overlap.
3. Every so often, interrupt the game and have one of the players calculate the area of the figure.

Helpful Tip: You may want to guide the players to build rectangles as they’ll make it easier to calculate the area. Stop the game at intervals when rectangles have been completed. Then, introduce the formula for finding the area of a rectangle: length x width= area.

Play this game multiple times and assign the cards several different values in order to get as much practice as possible.

TeacherTalk4all would like to thank education.com for being a guest blogger on our site and for sharing this activity with us. We think this game is engaging and a great way to introduce area at home or in the classroom. We are a supporter of education.com and thank them for all their dedication to helping teachers and students.

# Mystery Number Riddles

Mystery Number Jeopardy

During a math review game, I recently had a mystery number jeopardy section. The students loved the challenge and worked as a team to find the answer. I displayed each riddle and gave the students 30 seconds to complete the challenge. This was currently for a third grade class I was teaching. Feel free to use the riddles below.

100:

•  “I am a two digit number”
•  “I only have even digits.”
•  “My sum is 10.”
•  “The digit in the ten’s place is six more than the digit in the one’s place.”
• What is the mystery number?

200:

• I am a two digit number.
• I am an odd number.
•  The sum of my digits is 8.
• Both the digits are odd.
• What is the mystery number?

300:

• I am a three-digit number.
• Two of my digits are odd and one is even.
• 10-8=the digit in the one’s place
• The digit in the tens place is one more than the unit in the ones place
• The sum of all the three digits is 10.

400:

• I am a three-digit number.
• Two of my digits are odd and one digit is even
• The digit in the ones place and tens place combined is 9.
• The sum of the three digits is 18.

500:

• I am a three-digit number.
• All my digits are even
• The digit in the ones place is half of the digit in the tens place
• The digit in the tens place is doubled than the digit in the ones place
• The digits in the hundreds place is doubled than the digit in the tens place
• The sum of all the digits is 14