This really is more a loaf than a cake, so would be good toasted a few days after freshly cooked, or robust enough to freeze in slices for lunchboxes!
Take 1 cup of self raising flour, 1 cup of coconut, 1 cup of mixed fruit or nuts to taste, 1 cup of sugar and 1 cup of milk. Combine, stand for 10 minutes and then pour into a loaf tin and bake in a moderate oven for 45 minutes or until golden and a skewer inserted comes out dry.
Suggestions.... Substitute half the coconut for rolled oats or bran. I reduced the sugar to 2/3 cup and used brown sugar. For the fruit add finely chopped apple and a teaspoon of cinnamon. Try sultanas and walnuts (not for a nut free school!), craisins and sunflower seeds, finely chopped zucchini and mixed fruit and nut... Get creative!