Maths Workshop for Year 2 Parents and Carers 14 th January 2016 What do you understand by: Multiplication? Division? What vocabulary can you think of that applies to each of them? What equipment, pictures or images can you think of that might help children when starting multiplication and division? X repeated addition eg 5 x 3 is the same as (equals) times lots of groups of multiplied by multiply times tables double Repeated subtraction eg 20 5 = 20 5 5 Divide Divided by Share Share equally Groups Lots Halve Children need to know: Each multiplication table from 0 x 2 to 12 x 2 0 x 5 to 12 x 5 0 x 10 to 12 x 10 They need to be able to count in 2s, 5s and 10s, forwards and backwards at least to the end of that table, and ideally to 100 for 2 and 5. They need to know facts such as 2 more than 14, 5 less than 25. They also need to be able to answer questions quickly such as What is 10 times 5? Twelve lots of 10? How many groups of 2 in 22? How many fives in 45? These are multiplication and division facts. Write the answers: 8 times 10? How many 2s in 18? What are nine groups of five? Sixteen is how many groups of two? What is 8 multiplied by 5? Divide 120 by 10. Seven twos are... ? How many 10s in 50? Children need to know whether a number is even or odd to know what will happen when it is multiplied or divided. They need to know that even numbers will... end in 2, 4, 6, 8 or 0. And odd numbers will... end in 1, 3, 5, 7 or 9. This means multiplication statements for up to 12 x. For example: 10 x 5 = 50 5 x 10 = 50 50 10 = 5 50 5 = 10 Try this! Write the multiplication and corresponding division statements for: 8 and 5 6 and 10 8 x 5 = 40 5 x 8 = 5 = 8 40 8 = 5 6 x 10 = x 6 = 6 = 10 = 6 Use x = to make these correct 6 5 30 8 2 4 100 10 10 Use 5 8 and 40 to make these correct x = = 8 x 5 = 40 or 5 x 8 = 8 = 5 or 40 5 = 8 6 x 5 = 30 8 2 = 4 or 8 = 2 x = 10 x 10 or 100 10 = 10 Commutative a tricky word that children in Year 2 are not expected to know but they do need to understand the idea behind it. Addition and multiplication are commutative operations. This means that for these operations the numbers can be added or multiplied in any order and the answer will still be the same. So = 12 is the same as = 12 And 8 x 5 gives the same answer as 5 x 8. But subtraction and division are not commutative. 8 4 (= 4) is not the same as 4 8. (= -4) And 40 5 (= 8) is not the same as 5 40 (= 0.125) Children need to be taught this they dont automatically know or recognise it, and often wont notice or realise that they have written the calculation the wrong way round. Try these calculations for yourself just to check what happens... 8 x 10 = 10 x 8 = 50 10 = 10 50 = Problems word problems or problems involving reasoning or working things out from known facts. Contexts might mean using multiplication and division in other subjects, such as science, PE or history. Could be problems involving measures, mass/weight, height/length, data, money. The multiplications for this array would be 4 x 2 = 8 What is the multiplication sentence for this array? Oh dear! The naughty pup has chewed some of Sams stamps. How many stamps did Sam have to start with? = 10 5 groups of 2 or 5 x 2 = 10 2 multiplied by 5 or 5 multiplied by 2 5 pairs 5 hops of = 30 6 groups of 5 or 6 x 5 = 30 5 multiplied by 6 or 6 multiplied by 5 6 groups of 5 6 hops of 5 10p + 10p + 10p +10p + 10p = 50p 5 times 10p = 50p 5 hops of 10p 5 x 10p = 50p Multiplication and division are inverse operations. This means they are the reverse of each other. So an answer can always be checked by carrying out the calculation the other way round. 8 x 10 = 80 So, 80 10 = 8 or 80 8 = 10 One for you, and you and you and you and me. Keep going until they have all been used up. If there are any objects left over they are called the remainder. You can use any objects to represent the cakes, but ask a child to do this practically first using concrete objects helps make the connection between real objects and the symbols we use in maths. Keep taking out groups of the same number. How many groups are there? Any left over that wont make another group of the same number are the remainder. 8 x 5 = 24 2 = stickers How you can help at home Notice numbers all around us Practice counting up and back from different starting points, in 1s then in steps of different sizes Learn number bonds, number doubles and times tables Practice telling the time, knowing days of week, months of the year, noticing the date Familiarisation with coins, simple shopping bills, value for money offers in shops Measures g, kg, ml, l, cm, m Playing board games such as Yahtzee, Monopoly, snakes and ladders, card games, dominoes. years/multiplication-and-divisionyears/multiplication-and-division games.htmlgames.html