We buy meat and some vegetables from a local farmer. It is important for kids.
Beyond that, it is useful for parents to look at a check list of the foods with the highest chemical loads.(its online) Just forget about buying non-organic peaches, strawberries, lettuce, rice, raisins for the kids. It doesn't cost much to buy organic raisins and rice. I think the meat is important, too, but if you don't buy it direct from a farmer, it is wickedly expensive