I bought some front-opening deep A4 photo frames which hold 50-150 kids' drawings. It's a really nice way of keeping their art without being overwhelmed by it.
I am paperless wherever possible and have set up a load of email rules in Gmail to sweep regular bills etc into folders, but to keep them unread. I then check unread emails periodically to make sure I'm paying the milkman etc.
I have two small runner's rucksacks, with the bladder removed. One's for my work and course and contains a spare laptop charger, phone charger, pencil case, slim notebook, tissues, antibac (not a massive user of it but you never know), sanpro and paracetamol/ibuprofen. All I have to do when I leave for work or uni is put my laptop and a water bottle/coffee cup in there. Phone is in a wallet with my cards and cash (appreciate some people might be anxious about risk but it's better for me than having to try and remember different wallets).
The other bag is for my 6 year old and contains: 1 change of clothes including 2 pairs of undies and socks, wet wipes, a light coat for her that rolls up neatly, tissues, dog poo type bags (for dirty pants or other unmentionables), Calpol sachets, her water bottle, phone charger, any snacks, antibac, colouring pencils and activity books/drawing paper. In the winter I add spare hat and gloves. I also have a pencil sharpener in there it's not very good.
I bought some Tiles - a credit card one for my wallet, a tag for my keys and a round one which I stuck on the Amazon Firestick as we keep losing it. I really like being able to phone my keys and remote! (I don't use the wallet one now as my phone is in there.)
I also got the child a really good pencil sharpener for home - a heavy-duty stand-up rotary one. No more blisters!