Using Subtraction and Addition - The Complete Series (5 lessons)

Each included lesson focuses on a different aspect of addition and subtraction calculations, such as rounding and adjusting when adding mentally, using equal addition when subtracting, estimating by rounding and learning strategies for finding answers to calculations resulting in negative numbers.

There are plenty of opportunities for children to look closely at the numbers involved in a calculation and decide on the most appropriate methods accordingly. There's also a number of word problems and 'real-world' scenarios where children can apply what they've learned and consider whether an estimated answer, in some contexts, is acceptable. There's even a number of games and pairs/group challenges included – they're the perfect way to consolidate your class's learning and help them increase the speed and accuracy of their calculations!

Remind your class of some strategies to use when solving addition and subtraction calculations mentally: rounding and adjusting, and using equal addition. How do we know which methods to use when trying to solve calculations? The included slides address this question, suggesting ways of determining when written methods may be more appropriate. After that, there's a choice of activities: either practise sorting and solving mentally or written using the differentiated worksheets, or play a familiar game to increase speed, accuracy and confidence when calculating!

How do we know the best method to use when calculating? The included slides with this lesson recap using equal addition when calculating mentally, then go on to show how equal addition may also be used with a written method. After that, it's up to your children to determine whether a standard written method, or one of the equal addition methods shown is most appropriate for them to use as they practise solving a variety of calculations including some with five- and six-digit numbers and some with up to two decimal places.

Recap how rounding to various degrees of accuracy may be used to either predict or check answers to addition and subtraction calculations, and how to determine what degree of accuracy may be most appropriate. Building on this, the included slides explain that in some 'real-world' scenarios it is not always necessary to calculate an exact answer; an estimate may be acceptable. Children are then challenged to identify vocabulary in word problems which suggests that an estimated answer may be acceptable, or estimate by rounding to quickly draw up a shopping list for a chef's kitchen.

How can we solve subtraction calculations resulting in negative numbers? The included slides recap some methods for solving when the numbers involved are relatively small. They go on to explain an ad hoc method children may use to find negative number answers of any size. Following this, it's up to you! During either of the two included activities children will practise this method, with the option to sequence negative numbers in value order, too.

Having spent the previous lessons building upon their flourishing skills for solving addition and subtraction calculations, children will firstly recap what has been learned through responding to the questions and tasks on the included slides. They are then challenged to apply what they've learned as they either play a fun addition and subtraction calculation game, or work in pairs/groups on an addition and subtraction maths investigation activity.