More than 4,000 primary-school pupils are expected to sign up for an expanded nature-education programme by the National Geographic Channel this year.

Environment and Water Resources Minister Vivian Balakrishnan launched the 2014 edition of the National Geographic Channel Young Explorers Programme at the Botanic Gardens on Friday.

Dr Balakrishnan said of exploring nature: "The best things in life are actually free...the memories that you create from living, from interacting, from coming here with your family and friends."

The programme takes 7 to 10-year-olds on nature trails around Singapore, such as at the Botanic Gardens and Bottle Tree Park, and culminates in a nature camp in Borneo for selected ones who complete an activity workbook.

In its first year last year, about 2,300 pupils signed up.

More information is available at www.ngcyoungexplorer.com.sg.