Frost a cooled cupcake (baked from your favorite recipe) with green frosting, then mark the yard lines with white decorators’ gel.
For a pennant, wrap a fruit leather triangle around a pretzel stick and plant it in the field as shown.
Set a chocolate-covered almond or brown almond M&M football topped with white decorators’ gel laces on the field.
You can use your favorite team’s colors to take it up a notch.