Why is the Hair Green?

I'm trying a few new colouring techniques that I hope will make me improve.
Looks like I'll have to work harder
Oh, background is credit to my wonderful photography loving nee-chan.

Remember my website assignment a few entries ago?
Turns out I actually HAVE to do the movie website thing.
I just had it completed and sent to my lecturer today.
Here's how one of it looks like:

Okay, that's like so definitely Bonnie Wright but who cares right?
I just needed a victim who I can manipulate.
Wha- that came out wrong!
Okay, I'm not gonna elaborate a lot on my boring website but here's a few pics that I used for my website:

left is PS-ed, right is original

left is original; right is PS-ed
Yes, that's Emma Watson.
I would like to say sorry to the actor herself and all her fans because I coloured her hair green(of all colours) and made her look like a ghost(there's a reason for that)
It is not for commercial use so I think I shouldn't be sued or sent hate-mails.
This is all done in the name of getting good marks for my subject.
Again, I apologize.
but I do like how it turned out with this one.

Another with Emma. The green hair actually kinda looks quite natural
Lol

Another with Bonnie. Like I mentioned in a previous post;
This...is what you call red-haired.

This one, I don't really know why but I absolutely like how it turned out.
Maybe it's because I spend quite some time working on getting her hair to blend but I did have to erase a few of those straying ones.
I'm not pro after all.
I'm just a student.
Again, pictures used are not for commercial use. Please do not reuse or spread them around. Just link back.

So, like, what do you think about it?
I hope I won't have to do something like this again in the future.
And, anyone wants me to have their hair or any part of their body coloured in PS?
I'd be glad to render it for you.
I'm quite free anyway, now that this final assignment is already out of the way.
Your payment is only a day worth of public transportation fee to and from college.
That's like, RM 3.80
Damn, I actually calculated that using the calculator.
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Let me colour your hair purple!
Please, I beg you!