In fact, no harm to hang around with nothing to do or just day dreaming. Kids need time for day dreaming. In the old days, when we don't have mobile phone, when we don't have computer, it's really some people are innovative enough to imagine of special devices in future and now we have the mobile phone and computer. Not sure if I remember correctly a book we read in the past - 1948 - described what and how it would be in 1984. It said "in future" we probably talk with a box at the street and some devices similar to computers nowadays. Correct me if I am wrong, really read this book long time ago.
Just wonder in future, how many of our kids nowadays will become Bill Gate...
Though I am also a working mum, I strongly support the idea of half day school, no matter in the morning session or afternoon session.