They are a slightly off the beaten path collectible silk (actually satin) designated S21. They were available in the 1911-1914 timeframe as inserts and as premiums. I included a link to the NS gallery for you. I have a "set" of "types" - all of the schools and all of the individual sports represented. Value depending on whether they still retain the 4 perimeter overlays (where the cutter was supposed to cut), are not trimmed, and no sewing holes. Figure from 10.00 - 75.00 with golf and base ball on the higher end. Some schools are tougher than others. Looking at your group above - figure about 140.00 retail. Mastro auctioned (or sold) a super uncut sheet with color bars for a handsome sum.
http://www1.coe.neu.edu/~dan/S22/go.html