Addition and subtraction - Subtract one- from two-digit numbers - Presentation

Lesson 11 of a mathematics series focuses on enhancing students' understanding of place value through the addition and subtraction of multiples of 100. This concept is introduced by asking students to define what a multiple of 100 is. The lesson then progresses with activities that utilise a place value grid to visually demonstrate how to add and subtract hundreds. Students are prompted to consider why using the column method may not be the most efficient way to add hundreds, and they are encouraged to notice patterns when adding or subtracting 100s from three-digit numbers. For example, they will explore how the hundreds digit is affected while the tens and ones remain unchanged.

Further activities provide practical applications of these skills. Students are given word problems involving saving money, where they must calculate how much one person has saved based on the amount another person has saved plus an additional sum. For instance, if Malachi has saved £688 and has £200 more than Leanna, students will subtract to find that Leanna has £488. The lesson continues with more complex problems and reasoning exercises where students are asked to create word problems based on given calculations, such as writing 'more than' and 'less than' scenarios for the calculation 845 minus 400. Independent work challenges students to complete calculations and reason through their answers, reinforcing their understanding of how adding and subtracting hundreds affects the overall number.