The Beast Of Prey(1978)

After a wolf had killed a sheep in their village, 12-year old Roland and his friend Hugo keep track of the predator. Roland wants to build a trap to capture the wolf alive. His father, on the other hand, wants to kill the animal with the hunting collective. Thus, father and son become rivals. Whereas his father takes leave from his job to lie in wait for the wolf, Roland ditches school and tinkers with his trap.