Thimble Summer is the one where the little girl living on a farm finds a thimble at the start of the summer and good things happen for the next few months (I think, I've only had chance to read the blurb!).

The Saturdays is the first of the books about the Melendy family; the others are The Four-Storey Mistake, Then There Were Five, and Spiderweb for Two. Are those the ones you had? (The editions I have are Puffin ones with beige covers.)