I’m super happy that I’ve just identified one of the books I’ve read as a kid!
The plot of the book goes as follows: There was a somewhat mischievous boy who enjoyed causing trouble for his family, and especially enjoyed hurting the farm animals. One day he somehow pissed off a gnome (or some magical tiny creature) and the gnome turned him into… well, a tiny size. The animals were thrilled to see him in that size and wanted revenge. Then he went on a migration trip with a flock of wild geese, and of course throughout this trip learned to behave better. I couldn’t search for the book before because I don’t remember the names of the characters, nor the author’s name. But today, on a whim I decided to spend a few minutes searching, and jeng jeng jeng… The Wonderful Adventure of Nils by Selma Lagerlof! Maybe I’ll be lucky and able to find it at the local library :).
I’m still searching for another book, so please tell me if you’ve got any suggestion. It’s about another mischievous boy (A) who came across a magical wish-granting matchbox. He was stupid enough to pretty much spent the matches on useless things for fun. Then he ran into boy B, who also owned magical matchboxes. Boy B used the last wish to wish for 42352423414 other magical matchboxes (yeah very against the usual wish-granting rule). Boy A was then somehow captured and pulled into a city that was created by boy B. No one else was there. It was linked to the real world by a mirror door. Boy A had to find a way to get back to his family. All I remember is that plot, so… many thanks if you can suggest the title!