July 5, 2014

Closest to 100 - Math game to practice addition!

This is a fun and simple game that lends itself to a variety of math topics, including 1- and 2-digit addition, place value, absolute value, and negative numbers. It’s great for practicing mental math and combinations to make 10. It also provides many great opportunities to have math talks to discuss strategy. My students love this game. It’s easy to learn, there’s no time pressure, and it’s not as directly competitive as other games can be, which helps some students thrive more.



Closest to 100

Math Skills Covered: Addition (2-digit numbers), place value, negative numbers (optional), combinations to make 10
Materials: Deck of cards, scoring sheet
# of Players: 

OBJECT OF THE GAME: Get the lowest overall score in the game by adding two 2-digit numbers to get as close to 100 as possible.

Prepare the deck:
Prepare your deck by removing all face cards (J, Q, K) from the deck. (Leave Aces and 10’s in.)

Remove Face cards

Special card values:
Aces = 1
10’s = 0


  1. Deal out 6 cards per player.
    Deal 6 cards per player
  2. Each player selects 4 cards from their hand to make two 2-digit numbers that add up to 100, or as close as they can get to it.
    Anyone can look at your cards
    What combinations can Tiffany make with the numbers 2, 6, 2, 7, 9, 4?
    29+ 67=96
    …Ah-hah! 76 + 24 = 100! Perfect!
  3. Players write down numbers and sum on score sheet. The score is how far away you are from 100. Since Tiffany’s total was exactly 100, she gets a score of 0!
    Round 1
  4. When both players are ready, they share their solutions and check each other’s work.
  5. Repeat for rounds 2-5.
    In the examples below, try looking at the cards on the left and come up with combinations closest to 100 before looking at my solutions on the right.
    Round 2:
    Round 2
    Oops, I just realized that I should have added 74 with 26 (instead of 28). Um. Let’s pretend I did that on purpose… because you see, this would be a great opportunity to discuss strategies with your child, such as noticing that your score is over by a bit, and reminding them to check if there is a way to lower it… =P

    Round 3:
    Round 3
    Round 4:
    Round 4
    In this case, I could have done 83+18, which would give me a score of 101. Both options add 1 to my score, so it doesn’t matter. However, if I were scoring with negatives (see in “Variations” section below), then 99 vs. 101 would actually matter.

    Round 5:
    Round 5
  6. At the end, add up all the points to get their Total Score.
    Get the final score
  7. The lowest score wins.



Q: Can I use just one card to make a 1-digit number?
A: No. The only way to make a 1-digit number is if you have a zero (remember, 10’s = 0 in this game), such as “0 7” in Round 3 above.

Q: What if I have all high cards, like all 8’s and 9’s?
A: You will have a really high score… 🙁

Q: What do I do when there are no more cards in the deck?
A: Shuffle all of the used cards and keep going.



Discuss Strategies

Just like in the game Tic-Tac-Toe Products (and most other games), there’s a great opportunity for learning in discussing strategy. Here are some possible things to look for and/or discuss with your child:

In this situation, 41+21=62 is actually preferable to 57+42=99 because it brings the total score closer to 0.

I hope you give this fun and easy game a try! It’s great mental math practice and of course kids have a ton of fun when you play together with them! Family game night, anybody?

See more fun math games in my series on Fun Math Games for Children!

4 responses to “Math Game: Closest to 100”

  1. Rachelle Wallace says:

    Love to get new math games with cards! Thank you!

  2. Dakota says:

    Ooh, this looks fun!