Central Library

10375 Little Patuxent Pkwy., Columbia. 410-313-7800.

•All Together Now. Saturdays, 10:15 and 11:30 a.m. All ages; 30 minutes.

•Cryptography 101. Learn techniques for secure communication as practiced in Edgar Allan Poe's "The Gold-bug." Ages 11-17. Registration required.

•Eclectic Evenings. Second Tuesdays, 7 p.m.

•English Conversation Club. Mondays, 10 a.m.; and Thursdays, 7:30 p.m. Practice speaking and understanding English in a group setting. Register before attending.

Halloween Costume Parade. Oct. 31, 6:45 p.m. All ages.

•Noontime. Third Thursdays, noon.

•Putting it all Together with Simple Machines. Fri., Oct. 18, 2 p.m. Experiment with six simple machines to build a complex contraption. Ages 9-10. Ticket required.

•Rudimentary Robots. Oct. 28, 7 p.m. Ages 11-17. Registration required.

East ColumbiaBranch

6600 Cradlerock Way, Columbia. 410-313-7700.

•All Together Now. Wednesdays, 10:15 and 11:15 a.m. All ages; 30 minutes.

•Black Fiction. First Saturdays, 1 p.m.

•Meet the Author: Vaddey Ratner. Tue., Oct. 22, 7 p.m. A survivor of the Khmer Rouge regime in Cambodia, Vaddey Ratner wrote The New York Times bestseller "In the Shadow of the Banyan." Registration required.

•Readers' Club. Tue., Oct. 22, 4 p.m. Drop-in after school to share books. Ages 8 and older.

•Rockin' Library. Fri., Oct. 18, 3 p.m. Learn to play instruments and sing by playing "Rocksmith" and 'Rockband 3." Ages 11-17.

•Romance. Third Wednesdays, 7 p.m.

•Share a Scare. Oct. 31, 10:15 and 11:30 a.m. Have a laugh with not-so-scary stories, songs and activities. Ages 3-5. Ticket required.

•Teen Investor. Wed., Oct. 23, 7 p.m. Students learn how to pick stocks to maximize returns. Ages 13-17.