This is an American film, but it focuses on youngsters at Halloween. I recall the "dog **** on fire", but I don't recall the last part. I'll go ahead and give it a try though I don't know when you were 12.
"Kenny & Company" aka "Kenny & Co." (1976)
The film covers several days in the life of Kenny, a typical 12-year-old, and his friends. Kenny goes through all the activities that most of us went through as kids as he and his friends prepare for Halloween. Along the way, Kenny deals with such childhood issues as bullies, the death of a pet and his first crush on a girl.
If you copy and paste this at YouTube, you can watch Part 1:
Kenny and co