If your class are guessing their answers without any thought to their addition and subtraction knowledge, they need this Year 3 Estimate Answers Reasoning and Problem Solving resource. This resource includes two problem-solving style questions and one reasoning style question, with two of each type for children to get their teeth stuck into. We've even got the differentiated sorted for you with three levels allowing choice and challenge in your class.

Use this resource following a set of varied fluency questions. You can find these in the accompanying resources in this lesson. Alternatively, you could encourage mathematical discussion and collaborative working by using it as a group or paired activity. No need to stress about the answers, as they're included too.