Subtraction Strategies: Jump, Split & MAB
Year 2 Mathematics Learning different ways to subtract Building confidence with numbers
Warm-Up: Addition & Place Value
Count by 10s from 20 to 100 Show 47 using base-ten blocks Quick addition: 23 + 15 What's the value of 6 in 67?
What is Subtraction?
Taking away from a number Finding the difference between numbers Making numbers smaller We can solve subtraction in different ways
Strategy 1: The Jump Strategy
Use a number line to 'jump' backwards Start at the bigger number Jump back by the amount you're subtracting Count where you land
Let's Try: Jump Strategy
Problem: 25 - 7 Start at 25 on the number line Jump back 7 spaces Where do you land?
Strategy 2: MAB (Base-Ten Blocks)
Use blocks to show the number Take away the amount you're subtracting Trade blocks when needed Count what's left
MAB Practice: 34 - 16
Show 34 with MAB blocks Try to take away 16 Do you need to trade? Count your answer
Strategy 3: Split Strategy
Break numbers into tens and units Subtract the parts separately Put the answer back together Check your work
Split Strategy Example: 45 - 23
{"left":"Split 45 into 40 + 5\nSplit 23 into 20 + 3\nSubtract tens: 40 - 20 = 20","right":"Subtract units: 5 - 3 = 2\nCombine: 20 + 2 = 22"}
Which Strategy Would You Use?
Problem: 52 - 18 Think about which strategy might work best Remember: Jump, MAB, or Split Try solving it your preferred way