T.S.
I'm not a teacher, but my son LOVED the Magic Treehouse series, often read new books the day they came out, and wishes that there were books like this for higher reading levels!
It's a shame your kids are not enjoying Charlotte's Web. E.B. White books are really great. My childrens' kindergarten teacher read Charlotte's Web to them, and they loved it...except for the really sad ending. My husband and I read Trumpet of the Swan and Stuart Little to our kids at this age, also a success.
I know one of the moms suggested Junie B Jones. I know kids love that series, but I dislike it because Junie speaks in incorrect English. She is supposed to sound like a kindergartener, but my kids never sounded so bad in kindergarten! I would think it would be difficult for an adult to read those books out loud. I was happy my son had no interest in them. but my daughter did, as did my nephew, and that was fine...just not my favorite.
Enjoy!