Multiplication and Division - Written Methods - Presentation

In the lesson centred on written methods for multiplication and division, students are introduced to formal techniques for solving multiplication problems. The lesson encourages learners to distinguish between written and mental methods of calculation, prompting a discussion on the differences between the two. A key activity involves using a number line to solve a practical problem: calculating the total number of children in a school with 6 classes, each containing 26 children. By breaking down the multiplication into more manageable parts, such as multiples of 10 and then adding the remaining units, students are guided to complete the number line and find the solution. For example, they calculate 10 times 6 is 60, and then add the product of 6 times 6 to reach the total.

Further activities in the lesson include using Base 10 and the part-whole model to solve multiplication problems. Students are presented with a problem such as 24 times 3 and are asked to complete the calculations by multiplying tens (T) and ones (O) separately before combining the results to find the final answer. This method is then applied to other multiplications, such as 36 times 3, 24 times 6, and 45 times 4. The lesson also incorporates reasoning tasks, where students must decide which multiplications they would compute mentally and which would require a written method, discussing their reasoning with a partner. Additionally, they are tasked with identifying and correcting mistakes in given calculations, such as an incorrect sum in a part-whole model, thus reinforcing their understanding of the written methods and their ability to evaluate the accuracy of their work.