Here is a cheap fun lunch idea
make your childs favorite sandwich then take any shape cookie cutter and cut out their sandwhich.
keep the outer ring of the sandwich, place fruit, crackers,pretzals or any other solid food you serve for lunch.
This makes for a fun lunch with no extra money involved. The best part is many times kids get bored with the same old sandwich,but when you make it look different it somehow becomes a totally different sandwich.