J’s teacher frequently reminded me that J’s school bag was too heavy. We therefore bought several very light weight ergonomic back packs but we still received the same comment. Eventually we bought a super duper light one, forgoing some of the desirable ergonomic features.
One morning, while I was peeking into the newly purchased item, I decided to use my sewing to add a spine-friendly design to it. By attaching an elastic band, the weight of books were now fixed close to her back.
It is now an extra light ergonomic ruck sack now!