Year 4

Mathematics WorkshopYear 5Helping your child with Maths calculations

1Think back to the Maths you were taught at primary school.In what situations do you use this Maths now?

Shopping estimating if you have enough moneyFinding 25% off in a saleSplitting the bill in a restaurantMeasuring for fitting at homeCooking times and temperaturesTiming journeysChanging currency

1999 A new approach to teaching Mathematics

Strong emphasis placed on mental strategies time allocated in all lessons

Children learn in different ways and prefer different methods

A real understanding of numbers

video clipArrow cards, place valueAsk1. Can I do this in my head?2. Could I use drawings or informal jottings to help me?3. Do I need to use a formal written method?4. Should I use a calculator?

ADDITIONHow would you calculate these? 256 + 627 =53523 +2346 =ADDITION EARLY STEPS1. Partitioning: E.g. 256 + 627 =Hundreds: 200 + 600 = 800Tens: 50 + 20 = 70Units:6 + 7 = 13800 + 70 + 13 = 883

ADDITION LATER STEPS2. Column addition: E.g. 53523 + 2346 = 5352353523 2346 + 2346 +Units 9 55869Tens 60Hundreds 800Thousands 5000Ten thousands 50000 Total 55869

Ensure the place value is correct i.e.T H T UFinal steps: Can the children APPLY these addition skills?Fred went to Bahrain to see the Grand Prix. He had AED6500 for the trip. It cost him AED480 for his ticket, AED2136 to stay 2 nights at a hotel, AED3449The exact same method is used when adding decimals . Just ensure that the decimal stays in the same place in the question and answer.for his flight and AED240 for food. Did he have enough money? 1 2 1 48021363449 240

6305

He had AED6500, he spent AED6305 so yes, he had enough money!

SUBTRACTIONHow would you calculate these? 873 - 791 = 8456 - 3938=SUBTRACTION EARLY STEPS1. Using an empty number line: E.g. 873 791 = (Count forward from the smaller number to the bigger)

+ 9 + 70 + 3 791 800 870 8739 + 70 + 3 = 82SUBTRACTION LATER STEPS2. Column subtraction e.g. 8456 3938 =

7000 1 40 18000 + 400 + 50 + 6 - 3000 + 900 + 30 + 8

4000 + 500 + 10 + 8 = 4518 7 1 4 18456 3938 -

451814Applying our subtracting skills

2.809.651.256.50I head to the sports shop with 20.00. I buy a cricket bat and a cricket ball. How Much change do I get? Step 1Step 2 1 9.65 20.00 - 10.90 1.25 += 9.10 10.90

MULTIPLICATION AND DIVISIONImportance of knowing times tables

Division facts E.g. if 5 x 7 = 35 then 35 7 = 517Multiplying and dividing by 10ThousandsHundredsTensUnits.1/10 tenths1/100 hundredths27.5.9368.27 10 = 2.7

5.9 x 10 = 59

368 10 = 36.8MULTIPLICATION EARLY STEPSUse known facts:

Use your times tables:E.g. 15 x 7 = 10 x 7 + 5 x 7 =

Use your doubling skills:E.g. 35 x 4 = 35 x 2 = 70 70 x 2 = 140MULTIPLICATION EARLY STEPS2. Grid Method E.g. 346 x 9x93002700403606542700 + 360 + 54 3114 1 120 72 x 38 16 8 x 2 560 8 x 70 60 30 x 2 + 2100 30 x 70 2736 13. Column method: e.g. 72 x 38MULTIPLICATION LATER STEPS 1 72 x 38 576 21602736 1 Applying your multiplication27 children pay AED 55 for a school trip to the planetarium. How much money is paid in total?

AED 10 was to pay to the bus company and the rest was to pay to the Planetarium. How much money did the planetarium take in total?

27 x 55

1000 + 100 + 350 + 35 = AED 1485 in total

x207501000350510035PART 2

10 x 27 = 270 for the buses

1485 270 = AED 1215 for the planetarium in totalDIVISION EARLY STEPS, CHUNKING196 6

196 - 180 (30 x 6) 16 - 12 (2 x 6) 4Answer: 32 remainder 4 or 32 r 4 196 60 (10 x 6) 136 60 (10 x 6) 76 60 (10 x 6) 16 12 (2 x 6) 424365 15 = 24 r5 2 4 r5 15 365 3 0 6 5 6 0 5 DIVISION MUCH LATER STEPSFinally:

24 r5 615 365Apply these division skillsA netball team is made up of 7 players. If 212 children turn up to a netball tournament, how many full teams could you make?

How many teams?212 7 = 212 70 (10 x 7)142 70 (10 x 7) 72 70 (10 x 7) 2

So you can make 30 full teams.

There will be 2 players left over.Is my answer sensible?1. Estimate the answer - can they round up the numbers to come up with a rough answer?E.g. 47 x 2 = Estimate: 50 x 2 = 100Once you have calculated the answer ask yourself, Is it close to the estimate?

2. Check the answer using the inverse - E.g. 47 x 2 = 94 so 94 2 = 47.

What now?www.gemslearninggateway.com - Notes from today- Helping you to help your child with Maths booklet - Calculation booklets with these methods explained in detail- Useful websites- Mental Maths passports jsmith@jpsdubai.sch.ae