What is the title of this book?

[heartnsoul]

This was a children's or young adult's book in my public school library (year 1965). Storyline: youngsters find a bridge in the forest and when they cross it they shrink and find themselves in a miniature kingdom.

[karenmac60]

I know it can't be because the year is wrong but it sounds like this
http://www.amazon.com/Bridge-Terabithia-Kather ine-Paterson/dp/0064401847