Ok it's been awhile since I've read some of these, so some might not be strictly feminist, but they're what I grew up with and gave me female characters to dream of being like:

The Little House on the Prairie series by Laura Ingalls Wilder, Stargirl by Jerry Spinelli, The Trixie Belden series by Julie Campbell, Little Women (UNABRIDGED--this is important) by Louisa May Alcott (as well as Old Fashioned Girl and 8 Cousins), Boston Jane by Jennifer Holm, Kaiulani: The People's Princess, Hawaii, 1889 by Ellen Emerson White, Somebody's Horse by Dorothy Nafus Morrison, Our Only May Amelia by Jennifer Holm, Sally Anne Thunder Anne Whirlwind Crockett (picture book) by Steven Kellogg, Victoria: May Blossom of Britannia, England, 1829 by Anna Kirwan, Julie of the Wolves by Jean Craighead George, The Sisters Grimm series by Michael Buckley, Roll of Thunder Hear My Cry by Mildred D. Taylor From the Mixed-up Files of Mrs. Basil E. Frankweiler by E. L. Konigsburg What Katy Did by Susan Coolidge Esperanza Rising by Pam Munoz Ryan Mandy by Julie Andrews (especially good for 7-11 years old--really piqued my imagination!) Quillworker (picture book) by Terri Cohlene The Ramona Quimby series The Girl of the Limberlost by Gene Stratton-Porter Island of the Blue Dolphins by Scott O'Dell Megan's Island by Willo Davis Roberts Anne Frank's Diary The Witch of Blackbird Pond by Elizabeth George Speare Matilda by Roald Dahl Daughter of the Pirate King and sequel Daughter of the Siren Queen by Tricia Levenseller The Girl Who Drank the Moon by Kelly Barnhill Breadcrumbs by Anne Ursu

Also echo Anne of Green Gables and Harry Potter and Harriet the Spy :D

Ada Twist, Scientist.

Depending on ages, the Anne of Green Gables series, The Secret Garden, Hunger Games series, Harry Potter (ok, not necessarily "feminist" but get them to love JKR)

The Perilous Gard by Elizabeth Marie Pope Graceling by Kristen Cashore Gone by Michael Grant

The last two titles become good series.

Harriet the Spy for younger readers.

Code Name Verity is a great one.

Mulan.