EDIT: If he blows up his high school, is he really going to go to Heaven? That plan makes no sense.
It doesn't stop there... Let's say, for whatever reason, you can blow up your high school and still get into Heaven... Do you really think God is going to let you in if you have plans to kill his son?
Let's say, for some reason, God does let you in - he's friggin' Jesus. Jesus in Heaven. I don't think you can kill him.
Now, let's say you blow up your school and want to kill Jesus - and God doesn't mind either one and lets you in. Then, let's say you do actually manage, somehow, to kill Jesus... again, he's friggin' Jesus. I think he can just come back from the dead... that's like his super-power or something.
And thus the title of "Worst plan ever"