They don't have to be perfect, it gives them a little character when they are all different. I really tried not to fix the ones Jack made since he was so excited to help. They are a tad messier but overall they look great.
I got the idea here from Christine on her blog, From An Igloo. She has lots of other great things on her blog that I can't wait to try - like sewing a scrappy clutch, and making flower hair barrettes.
Have fun making spider snacks with your kids!