@ucla_all_the_way: I think that your camp sounds like so much fun, you have done a great job!
On day 4 you are having a mission day and I see you are not sure what to do, have a look at my day 4 to get some ideas-even though mine is for high school you can simplify the tasks drastically to suit your elementary kids (I got my ideas from taebaekluke). And for your market play on day 5 to motivate them why don't you give them fake money as a reward everyday of the camp so that when market day comes they have "money" to buy things at the market, the kids who did well will have more money.
Hope that is helpful.