Visit the library to borrow books, look out for story-telling sessions at library or McDonald’s, have a picnic at the seaside or parks, go to Science Centre, Zoo, Bird Park, etc. Go Swimming, go Esplanade outdoor theatres to listen to free musical performances, walk at Gardens by the Bay
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Bring them outdoors, dairy farms / animals farms / vegetable farm
Malls and community centers have many activities
Go to some short course
Diy arts at home.
How old are they?
Baking session?