what nasty surprise awaits the children at the very end of the chapter ?

Which chapter are you referring to? 

Chappter 12 Aslan

well you see the children's father had already been tortured and warned by the incidents taking place in previous chaps after the trial of tom robinson but atticus dryly ignored him and said he would change with the weather. happenings were becuz of bob ewell( the evil guy) who had been against poor tom. he then said ' 1 down 2 to go' by that he meant judge taylor and atticus as atticus was against bob and had ashamed bob in all the court ending his small reputation. he vowed to get him even if it took him the end of his life. scout said'...and it was the last thing he did."

a paegant was held at the school of scout and jem. aunt alexandra was tired from the event's preparation and refused to escort them. atticus said he felt tired and wanted to read. so that left the 2 to go alone on an unwary journey with a nasty surprise round the corner. when they were returning back from the paegant bob ewell, drunk enough to attack harmless children, did exactly so and hurt poor jem, who was trying to protect his younger sister, so badly that his arm broke. poor scout who experienced the event with numbness saw someone save them and carry jem back home. later they discovered that their saviour was their neighbour boo radley.

can u plz confirm me that u have read it? if not then i am sorry for destroying your experience as it is best if u read on your own. this is an amazing astounding and mind blowing for all readers. still your curiousity is answered .