New to Iran (Tehran)

Hello,

we are moving to Iran in the coming months and we are trying to collect some more information. Is there a mailing list for foreigners or perhaps even a specialised one for parents? How about and expat playgroup for small children?
And can anyone tell what days are off for weekend? Friday and Saturday, or Thurs + Friday, or...? In international organisations that is.
Any help will be much appreciated.
Thanks in advance,

Eva