Explore the exciting unknown as Arden Theatre concludes its stage production of Hans Christian Andersen's tale

The Flea and the Professor.

A young professor loses everything with the exception of a flea who lives in his vest. They begin a circus act and ready themselves to tour the world. During their adventures, the heroic duo must overcome obstacles including shipwrecks and cannibals. The musical odyssey celebrates the thrill and mystery of the unknown. Showtimes are 10 a.m. and 7 p.m. Friday; noon and 4 p.m. Saturday and Sunday.

"The Flea and the Professor," 10 a.m. and 7 p.m. Friday at Arden Theatre on the F. Otto Haas Stage, 40 N. Second St. Additional performance times this weekend are noon and 4 p.m. Saturday and Sunday. Admission: $30-$32, $20-$22 for ages 12 to 18; and $16-$18 for children. For information, call 215-922-1122 or visit www.ardentheatre.org.

Fourth Annual West Park Arts Fest

On Saturday, West Park Cultural Center and the High School of the Future present the Fourth Annual West Park Arts Fest, an afternoon of youth performances and activities.

This festival, rain or shine from 11 a.m. to 5 p.m., will have indoor and outdoor activities at the High School of the Future. The indoor children's pavilion presents storytelling from Oni Lasana, and historical storytellers from Promise Ministries. Activities will include face painting and arts and crafts. Performing will be the Kensington CAPA Drumline, the Gideon School Band, the SOTF Jazz Band, and the Young Talents of Music, whose members are city youth. In honor of National Lemonade Days, there will be an Alex's Lemonade Stand called "Little Ladies Lemonade" hosted by second- and third-grade girls serving lemonade to support children with cancer. Tree House Books hosts a book giveaway for children and young adults.

School of the Future Drumline and Kyo Daiko will perform an improvised drum "call and response." Cellist Monica McIntyre will perform, as will stand-up comics from Mayor Karen, from Philly Improv Theater's house comedy improv team. Hip-hop dancers the Bulack Brothers from the Chosen Dance Company will perform. Fearless Hyenas Stunt Team will do a martial arts performance and the Take the Lead Dance Studio will give a free salsa lesson. The day will also feature a youth chess tournament sponsored by Brown's ShopRite and a poetry slam to close out the fest.

4th Annual West Park Arts Fest, 11 a.m. to 5 p.m. Saturday at Fairmount Park/School of the Future, 4021 Parkside Ave. Admission is free. Information: 215-473-7810 or www.westparkcultural.org.

County Fair at Smith

On Saturday, Smith: The Kids' Play Place in the Park and the Junior League of Philadelphia present the County Fair.

From 10 a.m. to 12:30 p.m., children and caregivers can enjoy activities including bubble blowing, face painting, and beanbag games. For ages 10 and younger.

County Fair at Smith, 10 a.m. to 12:30 p.m. Saturday at Smith: The Kids' Play Place in the Park, 33d and Oxford Streets, in East Fairmount Park just above Kelly Drive. Playhouse and playground hours are 10 a.m. to 4 p.m. Tuesdays through Sundays. The playground is for ages 10 and younger and the playhouse is for children 5 and younger. Children must be accompanied by an adult. Admission: Free. Information: 215-765-4325 or www.smithkidsplayplace.org.

Contact Monica Peters at mpeters@phillynews.com.