My school has been doing Market Day every month for over 12 years. The percentage is based on how much is sold. In past years we've made 15% per on average. Last year because of the recession we had some 15% months and some 10% months. Usually we bring in around $600 - 700 profit.
Another elementary school in our cluster teams up with us, so we split the profits with them.
We have a regular team of volunteers, and some of them are middle- and high-school students needing community service hours.
If you do Market Day, it's helpful to have a large freezer (preferably donated to the PTO/PTA) in which to store orders that can't be picked up the night they're delivered. This makes it possible for teachers to place orders but not have to stay late to pick up their food. They pay in advance and then just remove their orders from the freezer the next day.
People at our school love the Market Day foods so much that some families continue to order after their children move on to middle school.
One way we promote Market Day is by suggesting that parents purchase snacks for their child's classroom. We can order goldfish guppies, teddy grahams, pretzels, munch packs, cheese sticks, and more.
It's only 10%. We usually get about 300-400 dollars a month with it - not a lot but it all adds up. The hardest part about it is finding enough volunteers each month to unload the truck and pack up the orders (for us it takes about 5 people each month).
