Provide the specifics for why you are praising the student. Telling the student exactly what behavior he did well makes the feedback more meaningful. Use phrases such as "I have observed" and "I have noticed" to help you focus on the specific issue you are praising. State observations rather than mere interpretations; base all your praise on concrete actions that you observe.
Memorize a list of phrases to add variety to your praise. Using different words and expressions to describe students' actions in a positive way will help motivate them. Some example phrases include "You should be proud!," "You're a great example for others," and "You're catching on."
Express appreciation. Tell the students when they have helped the class or the teacher accomplish a task. Tell the students when they solve some problem or behave exceptionally well. Appreciation alone is praise. Appreciation shows the student that he is an important member of the classroom and that his actions are important and are noticed.
Comment on positive behavioral trends that you notice in each student. Tell your student, "I like how you ..." or "You are always so good at ...." These phrases show that you are paying attention to the student's long-term behavioral pattern, and that positive behavior is appreciated in the classroom.