Sweet dates and crunchy oats make these a natural for school lunches.
Sift together flour, baking powder, baking soda, cinnamon, and salt. In a separate bowl, cream the butter and sugar with an electric mixer until light. Beat in the eggs, one at a time. Add vanilla and blend in flour mixture. Beat in oats, dates, and nuts just until thoroughly blended. Shape into 4 logs about 7 inches long. Wrap in plastic and refrigerate until firm.
Adjust rack to lower third of oven and preheat oven to 350 degrees F. Slice each log into ⅛- to ¼-inch-thick rounds, and place 1 inch apart onto parchment-lined baking sheets. Bake for about 8 minutes, or until cookies are set and light tan on the bottom. Cool on a wire rack.