Fast forward six months... yesterday I did Tape Resist Paintings with tempera paint, painters tape, and actual canvases (these from Oriental Trading, which were actual decent quality!) for kids in grades K-3. It was great!
First, I had the kids cover their canvases in painters tape. A lot (if not, all) of them needed help with ripping it off the roll, which I hadn't considered at all! Luckily my group was on the small side (plus I had two moms sit in), so I was able to bounce around and help everyone with all of their necessary tape ripping. And it was even kind of funny when, after I ripped the tape, the kids then had to pull it off my fingers. We got a little giggle out of it.
As the kids finished their taping, I had them each move on to paint. I tried to encourage them to be as creative as possible: to mix colors, make patterns, etc. Some kids finished quickly; others were so excited by the prospect of color-mixing that they got distracted and it took them longer. One girl made the most beautiful colors (coral, ocean blue, army green, etc.) and one girl added a few drops of muddy water to each of her paints and got a cool, swirly look over everything. One girl made polka dots and one boy did splatter paint (although possibly by accident). I was really impressed by everyone's creativity!
A good amount of the paintings were too wet to take home right away so I set up a little drying corner on the floor.
I told most of the kids to peel the tape off after the paint dried so the lines would be a little straighter. Unfortunately, because some of the paintings were so wet, this meant peeling the tape off at home--which meant that I didn't get to actually see a lot of the finished projects!
BUT! I did get to see a few and they came out awesome! Here are two of them (and their two silly-faced, goofball creators):
What worked least: I haven't quite figured out how to make the tape lines really perfect. I advised the kids to (a) press the tape down firmly and (b) paint away from the tape instead of into the tape, but even still, a lot of the edges still got smeary. Even my sample had slightly smeared edges. Most of the kids didn't care (and probably didn't even notice), but one girl was a little upset that the lines looked messy and I don't know how I could have even changed that!
What worked best: I think this craft, done on canvas, was the absolutely perfect mix of process and product. The kids got to be really messy and creative, but still walked out with something cool. An older sibling even suggested I do this craft with tweens and I think I may just take her up on that in the fall!