Last week, I published a post all about number sense; what it is, how you can identify students with good or poor number sense, how you can help develop number sense in your students and a couple of activities you can use in your class. You can read more about this post here.
In a nutshell number sense is all about being able to use numbers and processes in flexible ways. You will notice that when you read more about number sense, the research also talks about the ability to use mental computation. This is being able to determine the answer to a calculation or problem in one’s head. If you have good mental computation you would not need to only rely on pencil and paper or a calculator to help you with your calculations or problems.
Over the years, I have tried various activities to assist my students develop good mental computation strategies. This involved modelling different strategies as well as talking about how an answer was reached. Of all the activities I have used in the class, the most effective one I have found was the card game Numero.
Have you heard of Numero or played this card game in your class?
What Is Numero?
Numero is a card game that you can use to help develop your students’ mental computation skills. What’s great about this game is that you can start very basic by only using the number cards (1-15), but you can also extend the game further by introducing wild cards (these include the operations, fraction/decimal/percentage and square root) and scoring. This is an important feature of this game as you are able to differentiate for the various abilities in your class. There are 3 basic rules for Numero, which are explained further below.
A Numero pack contains the following cards:
- 1-15 number cards (in 4 colours: red, green, blue and orange);
- 4 subtraction wild cards;
- 4 multiplication wild cards;
- 4 division wild cards;
- 13 fraction/percentage/decimal wild cards;
- Square, cube, square root and cube root wild cards;
- 2 blank cards (to use as replacements if any cards are lost); and
- 2 point scoring check list cards
Who Developed Numero?
Numero was developed in Australia by Rev. Frank Drysdale. Mr Drysdale suffered from Alzheimer’s disease and played many different games to keep ‘mentally fit’. The game was first presented at the annual conference of the Mathematical Association of Western Australia. You can read more about the history of the game here.
How Do You Play Numero?
It is best to learn Numero in pairs and only using the number cards (for junior primary only use the numbers 1-10 to begin). Each player is dealt 5 cards and then 2 cards are placed in the centre facing up (if you are playing with more than 2 people then you turn up the number of cards to match the number of players). Place the remainder of the pack face down in the centre. See the picture below.
The person who did not deal (or if more than 2 people are playing, the person to the left of the dealer) begins play. Each person plays a number card from his/her hand to the centre and this must be a take, a build or a discard. This is where the 3 golden rules come into play.
Golden Rule No. 1
Each turn, play one number card only from your hand: either a take, a build or a discard.
Golden Rule No. 2
When you build, you must have the answer to that build in your hand in a single card.
What Is A Take?
This is when you use a single number card from your hand and either match it directly to one in the centre or a combination of cards in the centre. The cards that you have taken from the centre and the one in your hand are placed face down near the player, as these are now the winning pile. In its simplest form, the player with the most cards at the end is the winner. The player then picks up cards from the pile faced down in the centre to restore his/her hand back to 5 cards.
With this rule it’s important to remember that when taking, you can only use 1 number card from your hand, but you can match this to as many cards that equal your card that are in the centre. See below for some examples.
In Example 1 you could play the 2 from the hand to match the 2 in the centre, thus winning 2 cards. However, there is a better take available. If you add the 2 cards in the centre, 7 + 2 to make 9, then you can use the 9 in your hand to take 2 cards, and thus winning 3 cards. Remember you can only use 1 number card from your hand, but as many in the centre that match your number card.
In Example 2 you could again just match the 9 from you hand with the 9 in the centre. The better option would be to play the 9 from your hand to match it to both sets. Add the 7 + 2 to match your 9 as well as matching the 9 in the centre.
Remember, you want your students to verbalise what they are doing, so you should model something like: “I know that 7 + 2 equals 9, so I am going to use the 9 in my hand to take that set, but also to take the 9 in the centre”.
What Is A Build?
Sometimes it is not possible to perform a take, so the next best option is to try and build. This is when you use a card from your hand and add this to a card (or combination of cards) in the centre. This essentially creates a new number, ready to take in the next round. See below for some further examples.
In example 3 you can use the 5 from your hand to build on the 7 to make a total of 12. When building students must say out loud what they are doing, 5 + 7 = 12. Remember you must have the answer to the build in your hand, so to prove this it is best that the player shows this card to the other players.
As you have now played a number card to build, it means that your turn is over and you cannot take this build until your next go. This means that if any other players have a card that matches this build, they are able to take it.
Also other players can further build by adding cards, as long as they have the answer to the new build in a single card. A build can never be broken up.
Example 4 shows how you can use the 2 cards in the centre to build on. You would say 7 + 1 = 8, 8 + 5 = 13. You have played the 1 number card from your hand (5) to build a new pile totalling the 13 that is in your hand, ready to take on your next turn.
What Is A Discard?
If you cannot take or build then you must discard 1 card from your hand to the centre cards. This is placed as a single card in the centre and not on top of any other cards. The player’s hand must again be restored back to 5 cards. See the example below.
Example 5 shows that you cannot perform a take or a build, but you have two 13s. It is best to discard one of these as you can then use it in your next turn to take. If you plan ahead with your discards it can work in your favour. If however, you do not have this option then it is always best to discard your lowest card as you may be able to use this later to build.
How Does The Game End?
The game is over when there are no cards left in the face down deck and 1 player has no cards left in his/her hand. I always ended the game a bit differently from the official rules, but both ways work. For your junior primary students, you then get each player to count how many cards are in his/her winning pile; the student with the most is the winner.
The official ending is similar but also includes:
- The cards left in the centre are added to the winning pile of the player who did the last take;
- Any cards left in a player’s hand are deducted from the winning pile; and
- Each player counts the cards in his/her winning pile and the player with the most is the winner.
So What About Golden Rule No. 3?
The first 2 rules are all you will need when playing Numero with only the number cards. It is best to master these first 2 rules and the number cards before moving on to Golden Rule 3 and the Wild Cards.
Golden Rules No. 3 is: Every wild card played from your hand gives you another turn and if that is a wild card, another turn.
I will not show examples of this rule in this post, but will address this rule and wild cards in a later post.
How Have I Used Numero In My Class?
Firstly, I strongly recommend that you purchase the A5 display Numero Cards. I have then used double sided magnetic tape on the back of each card so that I can then stick the cards to a whiteboard, as in the picture below.
Before using Numero it is important to model all stages of the game and show many examples. I have had students suggest possible takes and builds with different scenarios that are displayed. It is important that you have students verbalise the possible takes and builds for the scenarios, so that other students are exposed to different ways that numbers can be used for the different situations.
It is also essential that you have the golden rules displayed so that students can refer to these. I made very basic posters (as in the pictures below) that my students could refer to.
I found the best way to use Numero was for short sessions (between 5 – 20 min) on at least 3 days during the week. If I only had 5 minutes I would model a different scenario. When I had more time students were placed in groups of 3 or 4 to play a game. I would always give students a target to try and achieve, depending on what had been modelled previously. I always made time at the end of the game for students to come back together as a whole class and discuss whether they were able to achieve the target.
As mentioned previously I have found Numero to be the most effective way for students to practice using mental computation strategies. It is a fun game that can be differentiated for the abilities of your students. If you haven’t already, why not give it a go!
If you would like more information on Numero or to find out where to purchase the resources then visit the official Numero website here.
You can also download a free copy of the Instructors Guide here.
I’d love to hear from you in the comments below if you have used Numero in your class? Does your school have a Numero club?