Jumbo
This was a hard one to kick off with and get them thinking. You can't see on the working out but two groups used big piles of 10's frames to help out.
jumbo.docx | |
File Size: | 31 kb |
File Type: | docx |
Big Idea
Mutliplication facts we know (5x, 10x), repeated addition and repeated subtraction can be used to solve division problems.
Expected ResponsesUp in 20's
Down in 20's Can't start Can't add or subtract twenty Use 10x or 5x Use 4/5/ |
PlanWhen get to 100 - have you learnt something that can help? 5 x 20?
Let them keep going/is up for down easier? Show me what happened on the first day (GROUP so don't happen) Link to division Ref to Stages |
Planned Teacher Connections
Talk about stages, getting kids to link their thinking and working out to a stage and begin to appreciate what they need to do next. Repeated addition/subtraction (Stage 5) can be used to work out Mutliplication / Division problems but if you use 10x or 5x you are pushing into stage 6.
Ex 1
Repeated subtraction. Clearly Showing ideas. Logical. Slow. NS: get to 5x see taken away 100, how can that help to speed up?
Ex 2
Awareness of division. Aware that could be "chunked" 20+20 = 40 to speed up....NS 5x or 10x rather that 2x
Ex 3
Repeated Addition, Clear labeling to show logic of working out. NS: 5x or 10x link to facts
Ex 4 - Discussed as a class
Stage 5 repeated addition, discussed this as a class because I really liked the table they had used. Also there was a little 1/4 at the end for the left over 5.
Ex 5 - Discussed as a class
This was the main discussion - they did not get the right answer, subtracted the last 20??? Rather than adding an additional day... BUT this thinking showed the idea of grouping the 20's in 5 to make 100. NS: once we work out 5 x 20 = 100, how can we start recording differently / more efficiently?