Fix It Morgan Is a Tennis Coach Who Wants to Know How

Fix It
Morgan is a tennis coach who wants to know how to be more effective in teaching her students so she studies her current group of beginning tennis students who are between the ages of 8 and 10 years. During the first week of lessons Morgan has the children play tennis without any instruction in order to assess their base level of ability. During the second week of lessons Morgan awards stars to students each time they use the proper forehand form. Morgan continues to do this until all the students use the proper form 75% of the time. After that she continues to give stars for good form, but gives them less frequently. Morgan finds that the kids continue to exhibit good forehand techniques and decides her positive reinforcement strategy is beneficial to the teaching of tennis and is making her a more effective coach.
What type of research design is Morgan using? Based on the information above, can you conclude that Morgan's method is causing the children to perform better?