I've illustrated many childrens' projects- books, advertising, and web.
Different age groups require a different touch- you can probably spot the difference between the 6-8 year old pictures as opposed to the early teen pictures.
It's important to be sensitive to the storyline and to the audience and to look further than just toeing a 'PC' line.
Research is often important- I once worked on a storyteller's website. My brief included a wide range of stories from around the world: Russian, African, Chinese and Malaysian. Sadly, that site is no longer available.
I've worked on educational publications and info-novels as well as fairy tales and fun.
Cute monsters are a specialty! I also work with living history and re-enactment groups, so much costume knowledge for period pieces is stored away.
I'm a comix artist, so a modern manga-esq approach is fine for work aimed at pre-teen and teens.