I like for students to have their own set of watercolors and I make them responsible for not contaminating the colors...by not cleaning the brush before using a different color. I also numbered my trays...and my seats were numbered...so I knew that the same person always got the same watercolor tray.
As far as pastels...they can be broken in smaller pieces and a box or two shared per table.
Thank you so much! So for items like pastels and watercolors, do you buy a set for each table, or do you buy one set for each student?