We go through phases, but we have a fairly steady routine right now:

Per week,
2-3 nights cooking from scratch
2 nights cooking from convenience items (like frozen ravioli, veggie burgers, etc)
1 night leftovers, random, or clean out the fridge
1-2 nights take out (or going out to eat)

What's it like at your house? Do you have a routine, or do you switch it up a lot?