Hi "Girls" - I think the thought is that, by continuing education year-round, the kids do not lose knowledge over the summer so that, in the end, it may be more cost-effective because teachers do not have to spend the first few months every fall re-teaching stuff from the previous year.
But I am curious to read a hub from someone that has researched the pros and cons of having kids attend school all year. Cost is probably a big factor, among other things. Thanks! Steph