I have done some lunch box planning today in readiness for Weds. Both of my DC get a bit bored with sandwiches so cheap and easy alternatives we often have are
Pasta, pesto, mozzarella, cherry tomatoes and chicken for DS if leftover from dinner
Aldi packet couscous with either some veg, meat, chorizo etc added (again usually leftover from night before)
Salad of new potatoes, hard boiled egg, tomato, cucumber, sometimes pepper (they don't really like leaves)
Frittata (great for using up whatever is in the fridge)
If there is leftover pizza they take that (though it is rare!)
Snacks include the usual babbel, fruit, crisps etc plus sometimes houmous and carrot / cucumber / pepper
This term I am planning on increasing the salad repertoire (for me and DH as well as the kids!)