Watch this video about good strategies for writing clear explanations of function rules. Pay attention to:

• 3 ways of explaining multiplication
• Using color and diagrams to make connections

Watch this video about specific things to look for in function rules. Pay attention to:

• n, n+1, n-1
• n²
• Gauss' formula
• subtracting missing pieces
• subtracting overlaps

Read these formulas and explanations given by some (7th? 6th? graders).

Apply the strategies from the first video to explain these formulas more clearly:

Pattern talk 9, student 1

Pattern talk 9, student 2

Pattern talk 9, student 3

Here is a page with the pattern reproduced 3 times that you could print out to help with writing your explanations.