I had one of those happy accidents yesterday in preparing this journal project. I had loaned out my glue stick box, and first kicked myself when trying to make my sample. I dug around and found some tacky stuff that you use to put up posters, and lo and behold, it worked great! Small amounts stuck to the paper without making sticky fingers, and it made the feather spines stay firmly in place. So try challenging your students to making art with real feathers, and see what they come up with.