I have been working on some problems to use with KS2 or KS3 that involve Number and number properties. I used the problems with a KS3 class today and I was quite pleased at the discussions students had. I gave them this task first.
The students were given time to discuss and many used whiteboards and trial and error to help them get a sense of what numbers could work, A few students commented on the fact that they needed to consider factors and even that the factors had to be common to two numbers. One students started writing the numbers in prime factor form. Most students started with 78 as it was a small number and quickly noticed factors such as; 2, 3, 13, 39, 78 and some noticed 26 and 6. Students realised that if they used 78 then the other numbers had to be 1 so this won’t work as 1 isn’t allowed. 78 = 3 x 2 x 13 so it did bring up some interesting discussions about the fact that all 3 were prime so as 1 couldn’t be used, 3, 2, 13 were the numbers that went in the grid and one they considered the fact that 13 was only a factor of 455 so had to be top right and 3 was only a factor of 96 so the order of 2, 3 and 13 was quite straightforward. I felt this activity did create some interesting discussions about types of number and their properties.
I gave students a chance to look at the following problems after…
Here is the ppt for the lesson and it included some student answers.