For that reason if the student does something positive, then show him and rejoice with him. This will strengthen the positive aspects and encourages the student to repeat those behaviors. On the contrary, if we always criticize what he do wrong, the student may fall into despair and arrive in the conviction that he he do not serve for nothing.
But that does not mean not to talk about of the mistakes on natural way and orient him to correct them, but with the intention to help, not to judge or condemn. Another aspect is to be realistic and comprehensive with the requirement of the children. You have to ask each one what they can reasonably give. If we requires too much can create frustration and if it requires less likely we can create a bum. We should talk with teachers to exchange opinions on the ability of students and what you can expect from them. One negative aspect of education is to make comparisons with siblings or with other friends.
As each child is different we can not ask them the same, and not to do comparisons because often produces jealousy and envy, it does nothing to help in the formation of personality or motivation for the study. It must avoid the unnecessary aid. What the student can do alone have to do it without our help.
Thus, the success will be his and increase his self-esteem and motivation. Adults can advise him with our views but not to forcibly impose our criteria. Sometimes it is advisable to reward good work with any material gift or emotional support, bearing in mind that praise the effort is always a profitable stimulus.