Originally Posted by
Peckish
I think I would make it worth her while to slow down. If she's old enough to use a sewing machine, she's old enough to learn how to use it responsibly. Either she can start doing things to earn money to pay for the new needles, or once the needle breaks, she can't sew for a couple of weeks because you have to wait for payday (or some similar logic) to buy a new needle.
I think it's sweet that she's sewing with you, but I don't think it's fair that you bear the cost of her recklessness.
I agree with Peckish, but would consider asking her parents to furnish the needles after explaining why, since you are teaching her a life skill that she will have forever, and not charging anything to do so. Also, if you do not have any twin needles to use, she will adapt to one needle, she can still do designs, just different ones. Adaptability is one of the best gifts you can give a child.