What would you draw for two thirds plus one quarter?
You will need 4 dice, 2 or 3 players, pen and paper each.
Start: You have 3 lives.
Each turn. Throw all 4 dice. Choose 2 of them and make the smallest fraction you can. For example, if you throw 3,3,4 and 6, the smallest fraction is 3/6 or 1/2. That is the number of lives you have to lose (by doing a subtraction).
You are dead: When the number of lives goes to zero, or goes negative. The winner is the last man standing….
Differentiation – one or all of the players may use a scientific calculator. It’s good practice in keying in fractions!
Questions to think about during the game:
- Who is winning? (Which is the bigger of 2 mixed numbers)
- How do “borrow” when you need to do so?
- You will need to think about common denominators. What is the largest one you may need?
- If you want to play a fast round, start with only 2 lives.
You will need:
- A game board each cancelling-fractions-gameboard
- A stack of game cards cancelling-fractions-cards
- A tables grid each noughts-and-crosses-tables
- Between 2 and 4 pupils.
- (or for more pupils and more challenge, cancelling fractions includung 11 and 12 tables)
- Play like this while they get used to the game.
- Give out a card, read the fraction, ask them if they have it on their board? (Probably they will say no)
- Ask which table both those numbers are found in? For example, if the card says 15/20, those two numbers are both in the 5 times table. Ask what position the 15 is in (answer, 3). What position is the 20 in (answer, 4). So, 15/20 is WORTH 3/4.
- The pupil covers 3/4 with the card.
- Take in turns until someone has 4 covered (or all covered, depending what pace you want).
- Play like this once they are really confident and getting bored with the pace…
- Hand out one card each, fast, they grab it and place it on their board. Commiserate if it is a duplicate that they don’t need “Oh no, not another one EQUIVALENT to 3/4!”. If they are pleased, celebrate “Great, you needed 2/9”. This gets the correct terminology bedded in, and also they see that fractions that are equivalent to each other generally LOOK really different.
- If 2 pupils draw (covering 4 fractions) have a tie break round with another card. At this pace, it works well to aim to cover all the factions up.
- If someone goes “bingo” check their board to make sure all the cards are in the right place.
Super Fast Round:
- Give each pupil 5 cards and see if anyone can go bingo.
Bonus level thinking:
- “You need one more card. What do you want to get?” Suppose it is 2/5. Point out they need a fraction made up of a “position 2, position 5” pair. Placing one finger in each position explains this nicely. It’s very gratifying if they get what they want straight away!
- Get the pupils to highlight the odd numbers before they start. Think about whether a fraction’s numbers are odd or even, or one of each, and which tables they should be looking in. Being hazy about the importance of odds and evens is common amongst struggling mathematicians.