I first set up the tables with a tray (I re-use a styrofoam one each year) that has at least two wide sections for red and yellow paint. Another small seperate tray with green paint (I use plastic lids from those giant plastic coffee containers). I also put out a fake poinsettia for reference. Our painting tools are unsharpened pencils and sponges cut into "petal" shapes.
We start off discussing the parts of a poinsettia, then I get into red and green being complementary colors. Students begin by choosing three separate locations on their paper where they would like to create their flowers. They use the eraser end of the pencils to stamp a 'cluster' of yellow dots on their chosen locations. Then they stamp the sponges into red paint and press around each yellow cluster to create the red "bracts" of their poinsettias. I love for them to keep white spots because it looks like "freshly fallen snow has landed on their flowers."
Lastly, we paint the negative space or background with the complementary color for red.. green! My students can finish this in one 40 minute class, however, this can be drawn into two sessions depending on how you present your information.
Each one is special and I'm eager to hang several around the school until I send them home for the holidays.
Red, yellow, and green tempera
Unsharpened pencils (or q-tips work too)
Sponges cut into petal shapes
9 x 12" or larger paper