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Here are a number of problems that will interfere with each other initially

simplify sum and/or product

Once we start to teach how to simplify h x h x h x h students lose their confidence  in knowing that h + h + h + h = 4h  .... so as soon as you teach h x h x h x h get students to work on and compare with h + h + h + h type problems, ideally in a mixed bag over time.

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simplifypq: h x h x h x h intro 

area

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and/or perimeter

With two concepts are ubiquitously confused by students such as area and perimeter, we know that after teaching one carefully - to what seems like mastery - when the other is introduced most students will become confused. We encourage students to embrace this confusion and encourage them to self reflect 

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If students believe that most people run into the confusion that they have encountered, and that there is a logical way through the problem, and that a pause for thought leads to an accurate answer and most importantly the students encounter as many instances in their timely practice assignments as required to accurately match the name of the concept with the concept then the teaching and learning process will succeed.

factor

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and/or multiple

Teach multiple typeOFnumber1.pdf but as soon as you begin to teach factor compare the two typeOFnumber2.pdf and give a hint of how to distinguish.

all the factors of ...

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and/or write ... as a product of its prime factors

Personally I like to teach students to write a number as its prime factors before I get them to find all the factors of the number.

factorPRIME - FACTORproductOFprime FFMcomparePPFM

HCF and/or LCM

factorPRIME - HCF 84 and 90 quick

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