In the 1985 movie Teen Wolf, when Scott Howard turned into a teen wolf, would he have had a human penis or a wolf penis?

Well, as usual with this kind of thing, the real answer is to ask the writer, because that's who really did the world building. I guess the director has a lot of influence too, but in this case, I kinda doubt they thought of this.

So, let's guesstimate!

In the movie, there are no significant skeletal changes. Now, this is ignoring the fact that it's all makeup, but we gotta pretend the character actually transformed, or this is no fun

It looks like body of the changes are muscle deep at most, with sone cellular level changes leading to enhanced strength, agility, and durability.

What does this mean for a penis?

Well, a penis, human or otherwise, is basically specialized muscle tissue (more or less, I ain't doing a tissue lecture here). So it is conceivable that there could be structural changes in that regard. And, since all of the changes are predominantly about hair, I think we can assume that the external features of the penis would be similarly changed. However, with no other significant skeletal changes, it is very unlikely a baculum would form.

So, this leaves us with a human looking penis, as in dangling from the front. It would likely be unusually hairy at the base, with some hair likely to extend up the shaft, since very hairy humans already have that sometimes.

It would likely also perform similar to a human penis, if not exactly the same.

Believe it or not, there is a genre called paranormal romance. That's basically magic entities banging humans or each other, but churched up a little. So there is a wide range of fiction where werewolf peen is discussed in detail. A good author knows the answer to this kind of question, even if it will never matter on the page/screen, because it's part and parcel of how and why the transformation works. They may not even consciously be aware they know the answer, but it's there in their head, or they end up making a lot of world building mistakes.

A werewolf is a cursed hybrid creature, so most likely he had a hybrid.

I think if you watch WolfCop... you might get your answer if it follows the same rules as Teen Wolf.

Don’t make me google what a wolf penis looks like… I’m just going to assume a dog is close enough.