Use frozen meal trays with compartments, and after every meal take the left over bits of your entree or your vegetables, etc... and fill the compartments. You don't have to fill the entire tray at once, just make sure they are foods that go together, even if they are from different meals.
I have even mixed up brownie mix and poured a bit into one compartment of each tray. It really does work. Your leftovers don't get pushed to the back of the refrigerator and forgotten and wasted, and you don't have to eat leftovers until you are sick of them.
Just make sure you label your meals, and before you know it, you will have a large supply of frozen microwave meals at a very low cost, and everyone can pick out their favorites.
If you are already buying frozen meals, save the plastic trays, there is no reason why you can't refill them.