NA2-1: Use simple additive strategies with whole numbers and fractions.
This means students will learn to treat whole numbers as units of ones that can be split and recombined to make calculations easier. Additive strategies are about a type of thinking not the operation of addition. So additive strategies can be applied to addition (for example, 47 + 38 is 50 + 40 – 5), subtraction (for example, 74 – 8 = as 74 – 4 – 4 = ), multiplication (for example, 4 x 4 = as 4 + 4 + 4 + 4 = , which is 8 + 8 = ), division (for example, 18 ÷ 3 = , as 5 + 5 + 5 = 15 so 6 + 6 + 6 = 18). Additive strategies may also be applied to finding fractions of sets particularly halves, thirds, quarters, fifths, eighths and tenths. Level Two corresponds to students being proficient at the Early Additive stage of the number framework.
- Find 1/4 and 3/4 of a set.
- Solve a problem by being systematic.
subtract 9
subtract 8
The purpose of this activity is to support students understanding that non-unit fractions are counts of unit fractions. For example, 3/4 = 1/4 + 1/4 + 1/4, meaning three quarters is three counts of one quarter.
- Solve addition problems like 8 + 4 = by going 8 + 2 = 10, 10 + 2 (more) = 12.
- Solve subtraction problems like 14 – 6 by going 14 – 4 = 10, 10 – 2 (more) = 8.
add and subtract numbers using the "through tens" strategy
- Students will be able to model a whole number as an array created from a set of equal groups.
- Students will be able to express the arrays they create as additive statements or multiplication statements.
- Students will be able to partition a number between 10-100.
- Students will be able to express a number between 10-100 as combinations and/or multiples of other numbers using a model and a mathematical equation.
explore different mental strategies for addition
Find fractions of a number
Use a variety of operations to solve problems
use addition and subtraction facts
use mental strategies to add numbers
find fractions of whole numbers
use a system to solvea combination problem (Problem 1)
solve addition problems using addition facts (Problem 2)
counter corners and edges in a 3 dimensional shape (Problem 3)
- Solve a story problem using multiplication facts of 2 and 4.
- Devise and use problem solving strategies (guess and check, guess and improve, act it out, draw a picture).
Solve division problems by sharing.
- Solve problems involving halves, quarters and thirds.
- Devise and use problem solving strategies to explore situations mathematically.
solve story problems involving sharing
Solve addition and subtraction problems by compensating with tidy numbers.
Change start-unknown problems to change-unknown problems.
Solve addition and subtraction problems by compensating with tidy numbers.
recognise visual patterns in tens frames
use "up to ten" strategy to solve problems
find a fraction of a region
find a fraction of a set
find rectangles within a shape (Problem 1)
solve problems using additive strategies (Problem 2)
continue a spatial pattern (Problem 3)
- Solve a problem by working backwards.
use additive strategies to add and subtract numbers to find costs and profits
use simple multiplicative strategies to solve problems
explore reflection patterns (Problems 1 and 2)
use additive strategies to solve problems (Problems 3 and 4)