In spite of all mishaps, slow beginnings, and a reluctant vat, it worked. The kids, rising 3rd graders, rose to it and I might have had a few questions except that they were inquisitive. So I was convinced.
Each class lasted about an hour with one small break between and I needed that to recoup, let the dye rest and grab a few bites. It was intense. I watched the time and just kept moving, mostly giving instruction and keeping an eye on the vat ( the teachers kept watch on their students) which was not doing its stellar thing. It worked well enough for satisfying results and the students gave their approval.
They practiced with at least two 9 by 9 inch muslin squares (if there was time, I gave them a 3rd). They were given string and rubberbands for binding in various ways. Some had never worked that way, but caught on quickly. After their smaller practice pieces, they were given a larger 12 x 16 in. piece(roughly) that they manipulated in the same way. Pieces went into a tub of water for soaking before going into the dye vat.
After that, it was like bees to honey. They wanted to help, help the pieces soak, put the pieces in the vat, unbind their pieces…anything they could think of and they loved the dye.