Addition and subtraction within 10 - Subtraction using the symbol - Presentation

In Lesson 17, young learners are introduced to the concept of subtraction using the subtraction symbol (−). The lesson builds on the previous day's learning, encouraging children to understand what subtraction means and to consider other words that convey the same concept. Students are prompted to discuss the meaning of subtraction and engage with the symbol through a series of activities. These activities involve completing number sentences, such as "7 − 2 = _____", and applying the subtraction concept to practical scenarios. For example, they are asked to calculate how many toy cars are left after some are given away, or how many bananas remain after several have been eaten.

The lesson includes various interactive elements, such as using counters or cubes to help solve problems and drawing images to represent the scenarios presented. Activities are structured to encourage reasoning and understanding of the subtraction process. For instance, students explore how to arrive at an answer of 1 by subtracting a number that is one less than the starting number, and why certain digits cannot be used in specific subtraction problems. Independent work tasks further challenge the students to find multiple solutions to problems and to identify patterns in their calculations. Throughout the lesson, there is an emphasis on understanding both the practical and abstract aspects of subtraction within 10.