This instructable is on how to make a K'nex soccer field. Here is the parts list:

Rods

Gray: 4
Red: 2
Blue: 12
White: 8
Green: 23
Orange (flexible): 4

Connectors

Yellow: 14
Orange: 6
Red: 16
Light Gray: 4
White: 2

The completed field:

Step 1: The Field

Build what this picture shows. If the picture is not clear leave a comment and I'll help you out.

Step 2: The Nets

Just build two of what this picture shows.

Step 3: Connecting the Nets

This picture shows how to connect the nets to the field. The green pins go into the holes on the orange connectors.

Step 4: Completed Soccer Field

So that's it for the soccer field. Make sure to comment if you had trouble and hope you enjoyed it! Just before going, to make sure you have everything right, here is the completed field again.