Students find the number of groups of a given size using division, reverse multiplication, trial and improvement, or iterative equal sharing. Students must show their working.
Students estimate a division problem, share their methods, discuss the nice numbers and factors method, and then do more problems using nice numbers and factors.
Students discuss making an interval estimate in multiplication problems (i.e., getting a lower and an upper limit for the actual answer using the front-end and rounding-up estimation methods). They then use this method on two problems.
Students discuss making an initial estimate in addition problems using the front-end method followed by compensation to get a more accurate estimate. They then use this method on two addition problems.
Task: Match vocabulary and definitions, and select why these terms are useful to know when thinking about butterflies at risk. Assessment focus: understanding science texts.
Students estimate an addition problem, share their methods, discuss grouping nice numbers, and then do a problem using this method, then design a question showing how it uses the method.