I really like Kidorable brand rain gear. As the name suggests they are for children and are just adorable. You can get matching rain boots, umbrellas, and rain coats for your little one and have a variety of designs to choose from. They also have backpacks, towels, sun hats, and other accessories to match the popular rain gear themes.
I know they hold up well. We used to pass my daughter's on to her cousin when she grew out of them. They lasted long enough to be passed down again to her little sister.