Preparation

Make paper cutouts in the shape of common articles of clothing usually worn by the children such as: white T-shirt, tie sneakers, blue jeans, red shirt, and so on. On each shape draw a large circle with a diagonal line through it (The NO sign)
Put signs in various places in the room where children either play at free choice time or for older students where they get or use certain items. For example in the lower grades put signs in the play areas such as the block corner and the water table. In the higher grades put signs by the paper, pencil sharpener, water fountain, and so on.

Procedure

Tell the students you have created new rules for the classroom. Anyone wearing that article of clothing on the sign may NOT use that area or item.
Avoid helping children find alternate choices or items. Ask: Why are you having trouble making a choice today?
At end of day have a class discussion. Some questions to ask:

Allow all children to express their feelings about the day. Then follow up by reading a book about Jim Crow laws such as White Socks Only (Coleman) or Goin’ Someplace Special (McKissack) or a book about discrimination such as The Sneetches (Suess) or Little Yellow Little Blue (Lioni)

Adapted from Barbara Thompson Words Can Hurt You. NY: Addison Wesley, 1993