They will love the batik. If you don't have time for that, just tie-dye will be popular. I teach middle school art, so I have lots of ideas.
One project my students really liked was beading. We went over the keys to character(respect, compassion, honesty, etc.) and they each chose a word that they felt they needed to work on. You could change this to "what you value." Then I gave them alphabet beads, colored plastic beads and beading elastic. They beaded a bracelet which they wore to remind them of their goals.
They also like building with popsicle sticks. You could make pirate treasure chests with sticks and plastic stick-on gems. Then they would have a place to keep their "booty" (the bracelet.)
It's not really a craft, but I've found that middle-schoolers, despite their attempts to look "cool" at all times, love to play dress-up. I don't call it that. It usually starts with a basket of fabric scraps and one brave boy to wrap a piece around themselves like a skirt. You could have pirate costume type fabrics and take photos of them. Then they could make scrapbooks or frames for their photos.