I'm just a huge fan of having soup in the fridge, ready to go, or in the crockpot. It's super fast and easy to pair it with cheese quesadillas in the evening. You can even make them more substantial, by putting in diced peppers, refried beans, etc...
Another go-to meal idea is salads, everything ready to go. Make a huge salad, and add boiled eggs, or ham/cheese.
Sub sandwiches are great, and everything can be pre-sliced and waiting for you at dinner time.
You can also make a couple of casseroles/lasagnas on the weekend, and eat from them all week.