The Farm Order Board is an NPC market run by Marie. She displays a grid of items that she wants to buy from you.

Marie starts you off with just 2 spots on the board. As you level up she adds more tiles until at 9th level there are 9 spots open. (3 by 3 grid) Marie pays you experience points and the base market price for each order you fill.

As you gain levels, Marie's orders get bigger. For example, Marie will ask for 8-12 apples instead of the 2-3 she asked for when you were a lower level.

The TOP ROW are always materials. I have seen her request:

Apple - Blueberries - Carrot - Corn - Honeycomb - Peach - Potato - Strawberry - Tomato - Wheat

Check the category page Farm Order Board for a complete list of everything that might be asked for by Marie.

At level 10, Marie will allow you to reject orders. You can reject an order by clicking on the "X" in the upper right corner of the cell on the farm order board. If you reject an order, Marie will place a new order in that spot after ten minutes. You can skip the ten minute wait by paying 2 keys.

At level 15 you will see the Sales Bonus Meter open up. Filling orders for Marie fills the bonus meter on the right of the farm order window. If you fill the bonus meter, before the time runs out, you enter a bonus round. The bonus round shows a picture of 9 crates, you select one and get the prize revealed. The sales bonus increases in levels as you fill orders. There are currently 20 levels and each level gives bigger prizes.

Zynga's Game Guide for the Farm Order Board

Zynga's Game Guide for CoOp Trading