This is something our family did last month, and it helped immensely with the number of times we went to the store as well as what we had budgeted for food.
Plan your meals a week in advance.
Have kids? Let them be involved too.
I know this sounds awful geeky to plan your supper meals this far in advance, but we've found that there isn't any guessing as to what we're having on any given night. And there is no running to the store for another pound of hamburger or a box of elbow macaroni. We already know what we're having and have prepared ahead of time.