I like the idea of using brown bags in the notebook. I think the original post was for younger children but I think it could easily be ramped up for an upper level group of children.
One fourth grade class at my school doing an animal research project in ELA (working in collaboration with what students are learning in science). I was thinking that the students could use index cards to take their notes while researching. They would use the note cards to write their paper in ELA but instead of throwing out the cards they could be "housed" inside these brown bags in their science notebooks.