There are almost no reports on the process of physical strength progress in Republic of Naval Academy in South Korea. In the present study, we investigated the shape of changes that occur, described a standard age curve for the four years, and attempted to build a model for evaluating improvements in physical strength by applying wavelet interpolation method (WIM). The subjects were 467 male students of the Korea Naval Academy in a suburb of Busan, South Korea. The 467 subjects included 134 first-year students, 116 second-year students, 113 third-year students, and 104 fourth-year students. In other words, the 467 subjects were used as cross-sectional data. The motor performance measurement included sidesteps, sit and reach, sargent jump, grip strength, push up, sit up, and maximal oxygen uptake ( V ˙O2max). The wavelet interpolation method was then applied to mean values for each physical strength item from the first to fourth years for items in which a significant difference was seen with ANOVA. After analyzing the pattern of physical strength improvements, standard values of mean ± 0.5 SD and mean ± 1.5 SD were determined with the mean and standard deviation in each year as the criterion, and the wavelet interpolation method was applied to those standard values. As shown in the growth distance curve depicted with wavelet interpolation, there were rapid increases in sidesteps, sargent jump, grip strength, and sit up until the third year. In the fourth year slight stagnation or a decreasing trend was seen. Push-ups increased rapidly until the second year and a slight increasing trend was seen even through the fourth year. In V ˙O2max, a larger decreasing trend was seen from the third to the fourth year. And models of those rising trends were constructed with the wavelet interpolation method. An evaluation chart was constructed from those constructed models. The evaluation model chart derived in this study can be used to evaluate trends in physical strength with each school year in individuals. If one plots one`s own physical strength records on this evaluation model chart, physical strength trends can be evaluated. If this evaluation system were introduced in the Naval Academy, it may contribute greatly to the educational system of the Academy.