There is a very interesting ongoing debate (propounded by @Dr Tomas Chamorro-Premuzic in his book) about competence vs confidence. In a business context competence is clearly the most valued attribute, though users who do not have this frequently mask it with confidence. But in school, and dealing with sometimes fragile egos, confidence can make a difference. According to this TES article “Showing belief in students increases their performance”. This concept is known as The Pygmalion Effect where research has shown that “there are ways to improve student performance, quickly and effectively, with minimal effort and without increasing the time you are spending on preparation.” The author then goes on to suggest 5 ways to motivate pupils: 1. Sharing a good piece of work that a pupil has done with the class; 2. Giving the pupils’ leadership roles; 3. Telling them that you believe in them; 4. Explaining to the class about how your expectations for them are high; 5. Not making work too easy or too hard. Using these tactics correctly can help “children feel that sense of achievement and growth”.
https://www.tes.com/news/school-success-achievement-believe-positivity-pygmalion