every single day is a ‘empty calories’ pudding choice (sponge, cookies, donuts, ice cream)
There are rules about what these are made with and be assured, they arent "empty calories". Children need carbohydrates, more so than adults, and these desserts often also provide necessary fats, vitamins (particularly the fat soluble vitamins) protein from milk & egg & calcium.
Those puddings are described the way they are to be palatable to children. You'll find they are made with nutritious ingredients including flours, eggs, dairy, fruit, veg like carrots, beetroot & courgette. If there's any sugar the quantity will be low as school dinners must meet specific guidelines in this respect.
People are so touchy about the term "pudding" or "dessert". Its a second course providing extra calories for growing children, its incredibly expensive to provide enough calories solely via things like meat/fish/fresh vegetables, wouldn't be a complete & healthy diet anyway.
These desserts can be prepared in advance with nutritious ingredients, are easy to transport, store & serve, and are palatable to children. They aren't an issue.