Sandy, I like to alter t-shirts….cut them off so they are shorter and rehem. I make designs with my ecal for an iron on transfer and viola I have a personalized t-shirt.
Now sewing on t-shirt material is not that easy…it tends to roll I'd find a pattern for a t-shirt to sew and use cotton duck or some other cotton fabric. Lots of patterns from Simplicity or DIY from patterns on the web, but you do have to figure out the size

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An just in case you want die cut you can use a simple image and cut the fabric on the cutter….using fusable backing or a stencil for painting, or a print on t-shirt transfer paper. Another thought is iron-on vinyl cut pieces.
Would love to see what she does! My 11 year old granddaughter took a sewing class at camp and made some pillows and a stuffed animal that was both machine and hand stitched. Lots of opportunities.
Oh and have you seen this technique for using Elmers Gel Glue and tie dye…very cool!
http://www.u-createcrafts.com/2011/08/c ... gle+Reader