Yeah, FB, but not MySpace - I went through the class of '70 yearbook, and anyone with an uncommon name, I looked them up in Facebook. I found about 15 or so likely matches, and sent out FB private messages to 11 of them, but received only three replies, and none of the three remember WF.
If you know the high school name why not google it and find any results for sites that people use to stay in touch with alumni from their school (classmates.com, myspace or facebook searching for the school name)?
Example - Search for xxxx High school via myspace/facebook and you will find a page for that school. People that went to that school at any point will often 'friend' or add that school to their accounts so you are able to see any people that have gone to that school..
Take myspace for example - the high school that I went to is REALLY small but when I do a myspace or facebook search for using my high school name I find a huge list of the alumni - You can then narrow those search results by searching for only the alumni that went through certain years or even searching for alumni by age.
Once you narrow it down the the people to the alumni that went to that school during the time frame that she did you could either email them one by one (or just email the administrator of the high school page) and see if they have any clue who she is? It just seems more likely to get results if you email everyone that went to the school you found her photo in at the time that she was there?
Also - Since it was class of 1970 that means that they would have just had a 4o year reunion, you could possibly email the school and see who was in charge of the reunion and see if they could be of help since its typically their job to find the alumni to notify them of a reunion.