Learn about 19th century ship life aboard the USS Constitution, celebrate the Very Hungry Caterpillar's 50th birthday, or enjoy music, demos and lots to eat at the Boston Local Food Festival.

Friday, September 14 

Learning Spanish Circle Time. Leominster Public Library, 30 West St., Leominster. 10-10:30 a.m. Learn new words, phrases, and songs in Spanish to build a Spanish vocabulary. For ages 3 to 5. Register ahead. Free. leominsterlibrary.org.

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.

In the Yard: Boston Navy Yard in the Civil War. USS Constitution Museum, Charlestown Navy Yard, Pier 1, Boston. 6:30-8 p.m. Discover how the Boston Navy Charlestown helped defeat the Confederacy during the Civil War. Free, donation suggested. ussconstitutionmuseum.org.

Broadway Princess Party. Berklee Performance Center, 136 Massachusetts Ave., Boston. 7:30 p.m. Brush off your tiara and unleash your inner princess with Broadway’s original Cinderella, Belle, and Jasmine, during royal ball of stories, sparkle, and sass. $47-67. berklee.edu/events.

Saturday, September 15 

In the Yard: 1812 Marines. USS Constitution Museum, Charlestown Navy Yard, Pier 1, Boston. 9 a.m.-3 p.m. Join the 1812 Marine Guard as you learn about ship life aboard vessels like the USS Constitution during the War of 1812. Free, donation suggested. ussconstitutionmuseum.org.

Festival of New England Makers. Old Sturbridge Village, 1 Old Sturbridge Village Rd., Sturbridge. 9:30 a.m.-4 p.m. Celebrate artisans, as the Village showcases New England trades from the 19th century including blacksmiths, potters, tinners, coopers, and more. Through Sunday. Free with admission. Adults $28, youth ages 4 and up $14, ages under 4 free. osv.org.

How to Make a Corner Bookmark. Leominster Public Library, 30 West St., Leominster. 10 a.m.-12 p.m. Learn how to make a cheery mouse bookmark for the corner of your book during this How-To Fair. For ages 3 and up. Free. leominsterlibrary.org.

International Red Panda Day. Franklin Park Zoo, 1 Franklin Park Rd., Boston. 10 a.m.-6 p.m. Learn about red pandas at our education station, partake in zookeeper encounters within the Children’s zoo, and celebrate our red panda residents. Free with admission. Members free; nonmember adults $19.95, children ages 2 to 12 $13.95, ages under 2 free. zoonewengland.org.

MFA Playdates: Autumn Light. Museum of Fine Arts: Boston, 465 Huntington Ave., Boston. 10:15-11 a.m. Enjoy story time and looking activities in the galleries followed by artmaking, take inspiration from the new Fall season. Recommended for ages 4 and under. Free with admission. Members free; nonmember adults $25, youth 7 and up $10, ages under 7 free. mfa.org.

Exploring Science Together: Owls. Harvard Museum of Natural History, 26 Oxford St., Cambridge. 10:30 a.m.-12 p.m. Study the secretive world of owls through hands-on activities about bird beaks and feet, dissect owl pellets, and more. Designed for elementary age students and family. Register ahead. Members $10, nonmembers $20. hmnh.harvard.edu.

The Very Hungry Caterpillar Turns 50. The Eric Carle Museum of Picture Book Art, 125 West Bay Rd., Amherst. 11 a.m.-3 p.m. A variety of programs in celebration of The Carle’s special exhibition featuring the Very Hungry Caterpillar itself, story time, refreshments, and more. Register ahead. Free with admission. Adults $9, youths $6, ages under 1 free. carlemuseum.org.

South Boston Street Festival. East Broadway between I and L Street, South Boston. 11 a.m.-4 p.m. Enjoy live entertainment on two stages, over 100 local merchants, artists, and organizations, children activities, great food, and family fun in this celebration of South Boston. southbostonstreetfestival.com.

Arms + Armor Demonstrations. Worcester Art Museum, 55 Salisbury St., Worcester. 11:30 a.m. & 2 p.m. Join us for this fun interactive program, and learn all about different kinds of arms and armor used by Roman soldiers, Medieval knights, and beyond. Free with admission. Members free; nonmember adults $16, youths ages 4 and up 46, ages under 4 free. worcesterart.org.

STEAM Expo. Newton Free Library, 330 Homer St., Newton. 12-3:30 p.m. Explore the concepts of Science, Technology, Engineering, Arts, and Math, and how these topics mix up together. Free. newtonfreelibrary.net.

Kosmic Kelly’s Hands On Science. Leominster Public Library, 30 West St., Leominster. 1-2:30 p.m. Join Kosmic Kelly to make your very own bug, and learn amazingly fun bug facts at Leominster University Jr. Free. leominsterlibrary.org.

Backyard and Beyond: Superfood – The Acorn. Discovery Museum, 177 Main St., Acton. 2-4 p.m. Come learn how to gather, dry, open, and make acorns edible, as they have long been throughout human history. Register ahead. Free with admission. Members free; nonmembers $14.50, ages under 1 free. discoveryacton.org.

Hispanic Heritage Month: Music and Dance Celebration. Worcester Public Library: Main Branch, 3 Salem Sq., Worcester. 2:30-3:30 p.m. Enjoy as Ritmos Academy kicks off Hispanic Heritage month through performances with colorful cultural costumes, and an energetic team of dance students. For ages 12 and under. Free. mywpl.org.

Learn to Create a Beautiful Mandala Rock. Leominster Library, 30 West St., Leominster. 3-4:30 p.m. Create a beautiful Mandala Rock featuring radial symmetry, color combinations, and meditative practice. For ages 4 and up. Free. leominsterlibrary.org.

Sunday, September 16 

Boston Local Food Festival. The Rose Kennedy Greenway, Boston. 11 a.m.-5 p.m. Enjoy one of the nation’s largest local and sustainable food hub, experience restaurants, food trucks, demos, local music, and more all with zero-waste. Free. bostonlocalfoodfestival.com.

ARTfull Explorations. deCordova Sculpture Park & Museum, 51 Sandy Pond Rd., Lincoln. 1-3 p.m. Investigate new ideas and unique materials inspired by the Sculpture Park artists, as we think dots, circles, and spheres. Designed for ages 5 to 12. Free with admission. Members free; nonmembers $14, ages 12 and under free. deCordova.org.

Caterpillar Creativity. The Eric Carle Museum of Picture Book Art, 125 West Bay Rd., Amherst. 1 p.m.-4 p.m. A special Sunday in the studio as we put together crafts inspired by the Very Hungry Caterpillar. Free with admission. Adults $9, youths $6, ages under 1 free. carlemuseum.org.

Boston Area Chantey & Maritime Sing. USS Constitution Museum, Charlestown Navy Yard, Pier 1, Boston. 2-5 p.m. Listen, learn, and lift your voices, as you participate in your maritime heritage by joining a rousing chorus of sea chanteys at the USS Constitution Museum. Free, donation suggested. ussconstitutionmuseum.org.