Aditi Mathur and Ratnesh Mathur

Hi, I am the Calculator. In the adult world, I’m fairly ubiquitous, in fact quite indispensable for many. But I miss children terribly. Also, I feel sad because when a child picks me up (a calculator), immediately I am put down as somebody who will spoil the child’s mathematical abilities and habits.

I do not really blame the adults for such a biased perception of my role in life and utter ignorance of my role in learning. After all computation, mental math and speed are considered of prime importance by many. However, in my opinion, the essence of mathematics is in conceptual understanding (and not in procedural competence). Hence, a mere tool like me can only aid in understanding of concepts. Also, used judiciously I can also help build procedural abilities.

I am not going to argue the above case – instead, I will show you examples of how you can use me to build both – conceptual understanding and procedural competence in children in their pre-primary and primary years. Once you see real examples of how valuable I can be I hope I will find my rightful place in mathematical development.

Before we start – please realize that I will be required to be given to and used by children only when they are doing these activities/games. They need not have a calculator at their disposal all the time. Also, for most of the activities mentioned here, a simple calculator is what is required (not the advanced one or the one available in mobile phones). Typically a school can have enough common calculators as activity resource in their math labs.

Games for children in the age group of 3-5

1. Explore calculator: This is more like a pre-activity. The idea is to give me (the calculator) to children and allow them to press the different keys and see what happens. Obviously, you’ll know – no matter what key combination they press – they cannot harm me!
2. Counting scorecard: This is used for simple counting (up to 8). For example one child aims a ring over an object and every time he succeeds, another child records success (score) by pressing any digit once. So if the child presses the digit 8 five times, he can count and call the score as “five”. We have played similar interesting games with the children coming to our learning centre often.
3. Dice digits: A game to reinforce the count (quantity) and digit (symbol) relationship. Use a dice with dots only. Child rolls – counts – and then enters the corresponding digit in the calculator. Since they are not forced to write – the children here can focus on the correct digit rather than correct way of writing it. If required, once the digit is confirmed – they can copy it on their note book.
4. Guess my number: A child presses any digit a few times. Ask the other to guess, “how many”. The other child presses some numbers in his calculator to show his guess. Then both compare. If both the quantity matches – they dance together

Games for children in the age group of 5-8 years

1. Reach me: Each child (or team) plays on their own calculator and speed is of essence. Everybody starts with same number (say 4). A target number is announced – say 71.Level 1 – Children (or team) have to add or subtract any number(s) to the number (4) and reach the target (71) as fast as possible.
   Level 2 – Children have to reach target number is exactly five steps.
   Level 3 – To bring in subtraction let your starting number be big (eg: 198) and target number be small (eg: 13)
   Level 4 – Multiplication and division can be brought in and target numbers can be much bigger numbers.
2. Got it: (Two players) After clearing the calculator’s memory, two players select a target, (say 23). Each child takes turns entering a number of their choice from 1 to 5. Every time a child chooses a number, she presses the memory-plus (M+) key. This stores the cumulative total in my (calculator’s) memory – while the children have to add and keep the total in their mind. When one of the players thinks she has reached the target (23) – she says “got it” and presses ‘Memory Recall’ button (MR) to check and, if correct, wins.
3. Score card: One simple way to use me (calculator) is to keep scores (for any other game). Children simply enter the number to be added and press the memory-plus (M+) key. Pressing Memory Recall button (MR), at any point gives the current cumulative total.
4. Checker calculator: One player rolls two dice, mentally adds them, writes down the sum. The same player rolls the dice again and adds it to the previous sum. The other player uses me (calculator) to check the sum. Switch roles. No time limit. No winner. This is just to reinforce addition skills using regrouping.
5. Table manners: Multiplication or multiples of any number is relatively easily available in me (calculator). All you have to do is to
   ~ enter the base number
   ~ press the + (plus) sign
   ~ followed by = (equal) sign.
   Now every subsequent press of = (equal) sign gives the next multiple of the base number. This simple way of getting multiples explores tables in many ways. One way is to determine – which number (between say 1-12) has how many multiples.
6. Except 1: A target number is taken (say 28). Using all the numbers on me (the calculator) – except 1 – find out in how many different ways you can reach the target number. The one who finds more ways is the winner. Or as a class try to find many ways. Variation: make different exception rules – like reach 55 – without using 5 – in minimum key presses.
7. As many: Take any two (or three) numbers. Now using any mathematical operations and only the chosen numbers (as many times as you want) – try to make as many different numbers – between say 1 and 50.
8. Number golf: Few target numbers (each number representing a hole on the golf course) are decided – say 52, 124 and 201. Now each player chooses any three (or two) numbers as ‘my numbers’ (Players can choose common numbers also). Now they add or subtract only their numbers to reach the first target number. The number of times they add or subtract is their score. They use me (calculator) to work this out (all the while) recording the number of ‘shots’ on paper. Whoever covered all the target numbers with the minimum steps is the winner, just like in golf!Eg: Player Mr. X chose 2, 5 and 50 >> Mr. X got 52 (1st hole) in 2 steps (50+2); Got 124 (2nd hole) in 8 steps (50+50+5+5+5+5+2+2); and got 201 (3rd hole) in 7 steps (50+50+50+50+5-2-2); So Mr. X’s total score is 17.

   But Ms. Y chose 1, 25, 100 >> Ms. Y got 52 (1st hole) in 4 steps (25+25+1+1); Got 124 (2nd hole) in 3 steps (100+25-1); and got 201 (3rd hole) also in 3 steps (100+100+1); So, Ms, Y’s total score is 10 (wins over Mr X). Can you beat both Mr. X and Ms. Y? Use me (calculator) and try.

9. Finding factors: Play this game, individually, in pairs or as whole class. Put any number (say 42) into the memory of your calculator and find which numbers divide it exactly. How many factors does 42 have? Try with other numbers up to 100. Can you find numbers with only 2 factors? (tabulate them). Can you find numbers with an odd number of factors? Is there a rule?
10. Meeting all friends: Using only 2, 3, +, -, x, and = (7 keys) can you make all the numbers till 20. Show how you did it. Try with other combinations and range.
11. Got it: Draw a grid of say 10 x10 and fill each square with numbers between 1-100. Each child tries to take turn and grab a square by showing on his calculator using only multiplication of two numbers. (x 1 is not allowed). (Use a specific colour token or crayon to grab a square). The player who grabs four squares in a row is the winner.

It’s quite obvious – that all the above games can have many variations. Encourage children to come up with their own variations and even their own games when they work with me (calculator). I enjoy being in the hands of children and making them think, analyze, guess, predict, win and yes, enjoy numbers.

The authors run Geniekids, a learning centre in Bangalore that works with children. To know more about their work visit www.geniekids.com.