In case you wanted to find other Facebook groups, I have started a list.. If you know of any not listed here, please let me know...
Class of 1970 -> https://www.facebook.com/groups/116811085377/
Class of 1971 -> https://www.facebook.com/groups/150973918341258/
Class of 1972 -> https://www.facebook.com/groups/161720530573704/
Class of 1973 -> https://www.facebook.com/groups/40715085717/
Class of 1977 -> https://www.facebook.com/groups/56477240974/
Class of 1978 -> https://www.facebook.com/groups/DHS78FL/
Class of 1979 -> https://www.facebook.com/groups/73234921489/
Class of 1984 -> https://www.facebook.com/groups/190029069417/
Class of 1986 -> https://www.facebook.com/groups/5415908415/
Class of 1994 -> https://www.facebook.com/groups/336979573028100/
Class of 2004 -> https://www.facebook.com/groups/202135249910557/
Class of 2006 -> https://www.facebook.com/groups/164763573687694/
Class of 2013 -> https://www.facebook.com/groups/198726016405/