Year 3 Term 2
Key Concepts – Number – Addition and Subtraction
Key Vocabulary – Addition and subtraction
Ones, tens, hundreds and thousands
How many more
How many less
Key Concepts – Perimeter
Key Vocabulary – Perimeter
Common Misconceptions – Addition and Subtraction
Children often thing that you can’t use counting on to solve subtraction calculations, - counting on is often the most effective method when numbers are close together.
That children do not understand the value of the whole number and rather see it as a series of singular numbers. This will cause problems when it comes to crossing boundaries.
That subtraction is not commutative and you are not able to take a larger number from a smaller number when working with positive numbers
Common Misconception – Perimeter
That children calculate perimeter by multiplying the length and width of a shape rather than adding the sides of the shape.
That children will not check the unit of measure for each side and therefore have errors in calculating their answer.
That children will put the start of the ruler at the beginning of a side to measure it rather than putting 0 at the start of the line.
That children can be confused by scaling – eg using 1cm to represent 1m and 1m to represent 1km (often used in worksheets)