I did a "Search" to see if this movie had been discussed, and the only thing that came up was it had been mentioned by several in another thread. Apparently it was a movie originally made in 1958 entitled "Teenagers Battle The Thing". In 1972 more footage was added, and retitled "Curse of Bigfoot".
The movie is available online to view, or download in several formats, it's in the Public Domain. It does take about a minute of download when viewing online before the video starts up so don't be too impatient, and of course you need a broadband connection dial-up won't cut it for viewing online.
I've only watched a few minutes of the opening and will be saving the pleasure (?) of watching it for some night when I have absolutely nothing else to do and won't mind possibly wasting 1 hour 28 minutes and 17 seconds of my life. You have to admit though, from the screen shot below of the "Bigfoot" from this movie, special effects spared no expense creating such a lifelike creature... hmmmmm... actually it looks like something concocted by a local 2nd grade art class as a project.
