I used this lesson in my 6th grade classroom, and wow--they totally got it! It was used after a unit on GCF/LCM, and it was a great next step to practice those skills, while doing something new.
This is a complete SmartBoard lesson that may take 1-2 days. The topic is the Common core standard: 6.NS.4, and the focus is on rewriting a sum as a product using the distributive property.
The lesson includes 8 slides:
warm-up (identifying common factors)
rationale (real-world examples)
direct instruction (step by step)
practice/check for understanding
More practice w/ word problems
Closure (word problem)