Here are a few examples of factoring puzzles:
Here's the same set up for factoring a trinomial.
Factoring with a > 1 is not much harder, when students remember to find factors of ac that add up to b. Those become the insides of this table, and factoring out GCF's leads to the outsides, and the final factors.
Worksheet - Table Puzzles (Multiplication)
Worksheet - Table Puzzles (Factoring)
My recorded lessons for these ideas can be found here:
Lesson 5a: Factoring Quadratic Expressions into Binomials
Lesson 5b: Table Puzzles (and Dividing Polynomials)
Lesson 5c: Factoring Trinomials