Good leisure bag for primary school children

Looking for a practical, yet send children backpack for a seven year old girl, I'm almost desperate. I did not want a mini version of "hiking rucksack" 'but for the upcoming class trip (day trips) it should be functional and beautiful. This medium-sized backpack has several small compartments and pockets so that sweater, water bottle, lunch box etc. can be accommodated. He is bigger than Kindergartenrucksäcke but smaller than normal backpacks. Ideal size for children of about 7-11 years for excursions. Only a chest strap may need to be upgraded so that the carrier does not slip off the shoulders.