Addition and Subtraction - Add two 4-digit numbers – more than one exchange - Presentation

The lesson on adding two 4-digit numbers with more than one exchange is an engaging exploration of arithmetic for students. It delves into the complexities of addition when multiple columns require carrying over numbers. Students are prompted to consider addition sentences that might result in more than one exchange, thereby deepening their understanding of the addition process. The lesson includes a variety of activities, such as using place value counters and written calculations to add numbers like 3423 and 3587. Through these exercises, students observe the 'chain' of exchanges that occur when the sum of digits in a column exceeds 9, necessitating an exchange to the next higher place value.

Further discussions in the lesson challenge students to critically assess statements about the addition process. For instance, a character named Malachi suggests that only one exchange is possible per column, leading to a maximum value of 18 in any given column. Students are encouraged to reason whether they agree with this statement and explain their thinking. Another character, Zach, proposes that there can be more than one correct answer for missing numbers in the hundreds column, prompting students to explore different possible solutions. To consolidate their learning, students are tasked with independent work, selecting calculations at varying levels of difficulty to solve in their books. Throughout the lesson, comparisons between the place value counter method and numeric representation are made, highlighting the importance of understanding the exchange process, such as turning ten ones into one ten or ten hundreds into one thousand.