(Some researchers ran) a workshop for low-performing seven graders at a New York City junior high school, teaching them about the brain and about effective study techniques. Half the group also received a presentation on memory, but the other half were given an explanation of how the brain changes as a result of effortful learning: that when you try hard and learn something new, the brain forms new connections, and these new connections, over time, make you smarter. This group was told that intellectual development is not the natural unfolding of intelligence but results from the new connections that are formed through effort and learning.
After the workshop, both groups of kids filtered back into their classwork. Their teachers were unaware that some had been taught that effortful learning changes the brain, but as the school year unfolded, those students adopted what (the researchers) call a "growth mindset," a belief that their intelligence was largely within their own control, and they went on to become much more aggressive learners and higher achievers than students from the first group, who continued to hold the conventional view, what (the researchers) called a "fixed mindset" that they're intellectual ability was set at birth by the natural talents they were born with.
(The) research had been triggered by curiosity over why some people become helpless when they encounter challenges and fail at them, whereas others respond to failure by trying new strategies and redoubling their effort. (They) found that a fundamental difference between the two responses lies in how a person attributes failure: those who attribute to their own inability-"I'm not intelligent"-become helpless. Those who interpret failure as a result of insufficient effort or an ineffective strategy dig deeper and try different approaches.
Peter C. Brown and Henry L. Roediger III,, Make It Stick: The Science of Successful Learning