Looks like a Schwinn Collegiate Sport (five speed) to me, however the fork looks rather Varsity like. If you go back into the 1977 catalog, your frame is not pictured, but if you look under the description you can see that the camelback frame was available in the 17” size only. The giveaway is the chainring. It’s much different than the one on the Varsity (a ten speed) which was also available with a camelback frame. The color is Sky Blue. Other then those two differences I gave you, they are essentially the same bike.