Watching this toddler try and try to stack cups is highly engaging

There is something so satisfying about watching this toddler struggle – and then finally succeed – in stacking her colorful nesting cups. After trial and error – and deep concentration – two-year-old Clarissa, who her mother says "was a little behind on certain things," celebrates her victory with excited squeals and dance moves. A nice reminder that it takes lots of "fails" to become a success.

Via Mashable