Collages series between artist and graphic designer Boris Peianov and photographer Dan B.
This is a great post by an art teacher who offers a variety of activities to teach collage -- including a session plan! Use it with Seniors earning their Collage badge (and note how some of the activities involve cooperative learning!)
Love this for a first project - identity collage
Fun Crafts Toddlers and Preschoolers Will Love
Fun Crafts Toddlers and Preschoolers Will Love: 3-Dimensional Numbers Collage