80's movie help guys!

[Alpha Sixx]

I have been trying to figure out the names of 2 movies I saw in the late 80's when I was a kid with my parents. The 1st I think may have been European. The story is some kids at a school get taken hostage by some men with costumes and masks If i remember corectly one of the men is dressed as santa clause. I remeber one scene where the men take the group along with the teacher and take over some elderly folks house and kill the old man and woman inside. They seem like they are out in the woods or a mountainous area. But finally at the end the children overpower them kill them and escape. And the final scene ends with some police showing up at their school to question them about the ordeal and the final scene closes with some jars that the children put the gunmens internal organs in after they killed them and got away.