Addition and subtraction - Add two-digit numbers not crossing 10 - Presentation

In a mathematics lesson geared towards enhancing fluency and reasoning in addition, students are taught how to add two-digit numbers without crossing the ten's threshold. The lesson utilises column addition as the primary method, instructing students to partition numbers into tens and ones to simplify the process. Emphasis is placed on the importance of aligning the columns correctly to ensure accurate calculations. Through a series of activities, learners are encouraged to dissect numbers into their constituent parts, thereby reinforcing their understanding of the base-10 number system and the fundamental principles of addition.

The lesson includes a range of engaging activities that prompt students to apply their knowledge practically. One task involves finding the sum of two two-digit numbers, such as 34 and 23, by breaking them down into tens and ones before combining them to reach the total. Another activity challenges students to visually represent their addition using base-10 blocks, aiding in the conceptualisation of the process. Real-life scenarios, such as calculating the total number of sweets or marbles that two individuals have together, provide context to the mathematical concepts and encourage students to represent and solve problems. Reasoning exercises further deepen understanding by asking learners to deduce missing digits in sums and to articulate their thought processes.