The Saturdays -The Melendy Quartet by Elizabeth Enright*

The Melendy siblings, Mona, Rush, Randy and Oliver, are tired of being bored on Saturdays.  So Randy suggests they poll their allowance money and take turns having an afternoon adventure by him/herself.  During these Saturday afternoon explorations in NYC, they discover interesting places and individuals.
A fun, sweet read!
*Highly recommend.
-Borrowed from the library.