Have you kept, for example, your old school exercise books? I went through them and kept a couple from classes I remember fondly lile English.
Text books from uni? Yes, I have some old textbooks on my shelf but mostly grammar books as I dod languages (so they coild come in useful).
Story books from your childhood? I have heaps, they are all out as I have kids but I will put in boxes and keep. I love them!
Your kids' clothes? I have kept quite a few baby clothes that I loved neatly in boxes, and things like ballet/Rainbow clothes but I have passed on others, otherwise my house would consist of nothing else.
Artwork / handicrafts made by kids? I have it all BUT at some point I will sort these. Not throwing it all away n omatter what Marie Kondo says!
Your DCs old school exercise books? Some but see above.
Christmas and birthday cards? I go through them every npw and then but actually, I love particular ones from people no longer with me.
Sentimental stuff e.g. cinema tickets, letters from friends, handmade gifts etc.? Um, yes!
Jewellery you don't wear anymore? Yes but I don't have lots.
Clothes that you're too fat for? No, I am ruthless about getting rid to charity of clothes I don't want or need.
Old bank statements? No.
Letters from HMRC etc.?
NO.
*Things "just in case" (e.g. 5 hole punchers)? No.
Loads of books? yes!