I'm sitting here in school on my slackware laptop.
I followed T3slider and in 5 min all was working.
Amazing support you all gave me so fast.
This I will do next time I have a big problem
I added some DNS servers into the /etc/hosts and
setup the proxy without the script. I tried that before without
the DNS servers in the /etc/hosts and i didn't worked.
but now I have learned something I can tell the schools admin...