Preheat oven to 350°F (175°C). Line baking sheets with parchment paper.
In a large bowl, cream together the butter and sugar until light and fluffy.
Beat in eggs one at a time, then mix in the vanilla.
In a separate bowl, whisk together flour, baking soda, baking powder, and salt.
Gradually add dry ingredients to the wet ingredients, mixing just until combined.
Fold in oats, rice cereal, and shredded coconut until evenly distributed.
Scoop dough onto prepared baking sheets, spacing about 2 inches apart.
Bake for 10–12 minutes, or until edges are lightly golden.
Cool on the pan for 5 minutes, then transfer to a wire rack to cool completely.