Yes, wet floors can be lethal - a friend of DD1's slipped over on one at KiGa after all the DC had been outside and chipped her tooth. The children have to wear slippers all year round at our KiGa as well; ABS socks (or whatever they're called) aren't allowed.
silken Would agree with everything that 5more said, although I've never dressed my DC in tights and trousers as it's just so warm inside our KiGa; I decided that they would be warm enough in just trousers, socks and snowsuits when they went out to play in the snow. (We had those snowsuits with a kind of stirrup at the bottom, avoiding the gap between trousers and socks that shocks so many Austrians - not ideal in the snow, I admit.)
I usually dress(ed) my DC in a vest and long-sleeved top (nothing too warm, due to above-mentioned indoor temperatures - I picked up DD2 to find her just wearing her vest once or twice, so 5more's T-shirt suggestion is sensible), and would then hang up a cardigan for them (if they were cold/went outside) and a coat and snowsuit, plus hat, gloves and scarf in their box.
Sorry your DS is ill, Cinders; there are lots of colds and bugs going round here atm as well. The boy who was here on Saturday, who had to leave because he wasn't feeling well, ended up developing a high temperature and stomach bug so I'm really hoping he hasn't passed it on to us (it's looking good so far, but the last bug we had seemed to have an incubation phase of four or five days).
5more Sorry to break this to you, but boys do have Freundschaftsbücher too - or at least they do here in Austria. DS had lots to fill in last year from both girls and boys (although he's never had one of his own) and both DDs had quite a few from boys in their first year of school. The only ones that DD1 gets now (4. Klasse) are from girls and they're much fewer and further between than they used to be; the "worst" years were probably the last year of KiGa and the first year of school.
I actually don't mind them atm as I can fill them in for DS and the girls are quite capable of writing in them alone, but DD2 always insisted on filling them in by herself at KiGa (DD1 didn't get them until she was at school) and it would take ages, esp. as she still needed help spelling most words so I would have to sit there the entire time. Oh yes, and those children that (apparently) insist they must have the book back by the next day are very annoying too!