9. Apply mental mathematics strategies and number properties, to determine with fluency, answers for basic multiplication facts to 81 and related division facts
Apply mental mathematics strategies for multiplication, such as:
Annexing then adding zero
Halving and doubling
Using the distributive property
Demonstrate, with and without concrete materials, an understanding of multiplication (2 digit by 2 digit) to solve problems.

10. Demonstrate, with and without concrete materials, an understanding of division ( 3 digit by 1 digit) and interpret remainders to solve problems
What is Grade 5 mathematics in the balloon problem?
Recognize we did not have enough: we know we were short 18. We know the whole, we don’t know some of the parts: missing addend
Remainder can be subtracted, subtraction strategies include seeing that 18 is close to 20, compensate: mental math since Grade 2: 2 digit numbers,
does not require paper and pencil
Dividing to find how many per bag: division is related to multiplication: This basic understanding must be there if students are going to move to algebra... It is not about subtraction or addition
Evidence/recognition that multiplication facts can help with division
120 is not a difficult number (25,s since grade 3, decomposing and place value)
Strategies for dividing should be focused on efficiency