I found this lesson on https://www.instagram.com/p/BmBwCtmH3e7/ when searching around for something besides a heart project to do for Jim Dine. It is a great lesson that kids of all ages seem to love. The charcoal shading is a touch of magic as well as the puddles of color.
Have students trace around the brush they are sharing with the student sitting next to them and free hand in the details (then the other student will do the same).
Continue moving the brushes around the tables until each student has traced 5 different paint brushes (they can lay them out however they want but I would suggest the 2nd grade do them all one direction and no overlapping). After they trace the outside they will free hand in the details (caution them to do this slowly and carefully and to really observe the details on the brushes).
As the students are waiting for a new brush to get to them they can begin carefully going over the brush drawings they already have with Sharpie, being careful to erase lines where the brushes overlap before they Sharpie. Complete with all 5 brushes, then have students erase pencil lines.
Talk to them about the charcoal vines and carefully demonstrate how to hold them and to press gently with them (they are very fragile and will break easily).
Using the charcoal have them slowly draw a thick line touching the right side of each brush, making sure to not draw over the top of a brush. Move around the computer paper to act as a shield for their fingers as they are doing the charcoal part.
Then have them gently smudge the charcoal pulling the charcoal away from the brush. Have them wipe their fingers often on a paper towel so as not to get charcoal fingerprints all over their paper.
Distribute the liquid watercolors and have them put one color on each brush tip, being careful to keep the paint on the brush bristles only. They should use the watercolor undiluted and put a “puddle” down then add some water if need to spread it. This is done by plopping the paint and patting the brush to the paper to make it look like a blob of paint. They should not “paint” the color on or they will not get the rounded edges of the paint puddle.
After they paint a color on a brush bristle, they will take that same color and add some water to their brush and paint some smaller puddles of paint in 3 or 4 places on their papers.
Repeat this process with all 5 colors.
Then with water on their brush they will add a little paint and very gently tap their brush over the picture to create dots. 2 or 3 taps for each color (make sure they don’t overdue this or there will be a mess).
When paint is completely dry quickly spray a light coating of workable fixative to “set” the charcoal.