I did a jungle party for DD's 3rd birthday. I just served pizza & cake but I do have some ideas. One easy one is to get some animal cookie cutters and cut out little sandwiches for the kids. You could even use them to cut out fruit animals using apples, melon or pears. Make jungle snack mix with dried cereal, pretzels, cheese crackers etc. Ants on a log (celery stuffed with peanut butter or cream cheese with raisins on top) is another idea.