Pirates, princesses and fairies... oh my! See what's happening this last weekend of September.

Friday, September 28 

Backyard and Beyond: Forest Fridays. Discovery Museum, 177 Main St., Acton. 10-10:45 a.m. No matter the weather, head outside and enjoy a nature-based activity based on the weather and season. Free with admission. Members free; nonmembers $14.50, ages under 1 free. discoveryacton.org.

Baby Bounce. Worcester Public Library: Main Branch, 3 Salem Sq., Worcester. 10-11 a.m. Get your little one bouncing and singing this story time just for babies with rhymes, songs, stories, bounces, and more. For ages up to 18 months. Free. mywpl.org.

Celtic Thunder. The Shubert Theatre, 265 Tremont St., Boston. 7:30 p.m. Enjoy this multi-platinum Irish group as it presents brand new music and favorite hits backed by the terrific Celtic Thunder Band. $48.50 and up. bochcenter.org.

Saturday, September 29 

Fairyborough Trail Hunt. Discovery Museum, 177 Main St., Acton. 9 a.m.-4:30 p.m. Head to the path to see if you can spot what’s out of place in our Fairyborough. Free with admission. Members free; nonmembers $14.50, ages under 1 free. discoveryacton.org.

Pirates and Princesses Day. Franklin Park Zoo, 1 Franklin Park Rd., Boston. 10 a.m.-6 p.m. Grab your favorite fairytale outfit and prepare for a fun-filled day at the zoo as you meet your favorite princesses and join Jack and the Pirates of the Rogues’ Armada. Free with admission. Members free; nonmember adults $19.95, children ages 2 to 12 $13.95, ages under 2 free. zoonewengland.org.

Happy Birthday, Mrs. Bradley. Eleanor Cabot Bradley Estate, 2468 Washington St., Canton. 11 a.m.-1 p.m. Celebrate Mrs. Bradley’s birthday with some of her favorite cookies, berries, and tea, as you pick a basket of your own and enjoy in the harvest festival. Register ahead. Members $5, nonmembers $10. thetrustees.org.

Drawing Paddington with R.W. Alley. The Eric Carle Museum of Picture Book Art, 125 West Bay Rd., Amherst. 1:30 p.m. Enjoy watching the illustrator for the Paddington books of the last twenty years demonstrate his craft as audiences draw along with him. Free with admission. Adults $9, youths $6, ages under 1 free. carlemuseum.org.

Solo. Newton Free Library, 330 Homer St., Newton. 2 p.m. Follow a young Han Solo as he teams of with Chewbacca and Lando Calrissian for his first smuggling mission. Free. newtonfreelibrary.net.

Sunday, September 30 

Sukkot Festival on the Farm. Powisset Farm, 37 Powisset St., Dover. 9 a.m.-12 p.m. Celebrate the agricultural roots of Sukkot, as we build and decorate a sukkah, help with the fall harvest, learn about honey bees, enjoy storytelling and singing, and more. Register ahead. $10. thetrustees.org.

Cars and Critters. Stone Zoo, 149 Pond St., Stoneham. 10 a.m.-6 p.m. Enjoy cars of all makes and models, along with music, trophies, and animal encounters. Free with admission. Members free; nonmember adults $17.95, children ages 2 to 12 $11.95, ages under 2 free. zoonewengland.org.

Children’s Book Illustration with Timothy Basil Ering. Museum of Fine Arts: Boston, 465 Huntington Ave., Boston. 12-3 p.m. Discover the inspiration and technique of illustrating children’s books with this award-winning illustrator known for his originality and inventiveness. Free with admission. Members free; nonmember adults $25, youth 7 and up $10, ages under 7 free. mfa.org.

48-Hour Theater Project. David Friend Recital Hall, 921 Boylston St., Boston. 7 p.m. With only two days for preparation, enjoy original 10-minute musicals written, directed, composed, performed, and produced by students in a two-day span. Free. berklee.edu/events.