The Time Machine Girls #1: Secrets

Don’t go in the attic...
When eight-year-old Hazel and her little sister, Bess, visit their grandparents’ farmhouse for the summer, they’re given one big rule to follow: Just don’t go in the attic.

Of course, that’s the first rule Bess breaks. And rule-following Hazel doesn’t have a choice. She knows it’s wrong to go in, but she has to get her sister out. And that’s when she discovers the reason behind the rule, a hidden time machine and a trunk full of stolen items from history.
It’s the beginning of a family mystery that takes the girls all through time to return stolen items while trying not to ruin history.
The first stop on this time travel adventure is to 1738 to meet a young George Washington and learn that you don’t have to wait to grow up to know you have what it takes to succeed in life.
Books in this series:
Secrets:
First stop: 1738 to meet a young George Washington, and learn that the qualities of leadership can show up at any age.
Never Give Up:
Second stop: 1879 to meet Thomas Edison, and learn that success often includes failure, and lots of it. The trick is to never give up.
Courage:
Third stop: 1849 to meet Harriet Tubman and learn that courage sometimes means taking the hard road in order to help everyone get on the right road.
Teamwork:
Fourth stop: 1916 to meet Marie Curie during WWI, and learn that we can all reach new heights when we all work together to get there.