The current research aimed at studying the effectiveness of a program based on developmental mathematics approach to develop higher order mathematical thinking levels and mathematics appreciation for primary stage students. Participants of the study included 53 students; 25 students as a control group and 28 students as an experimental group. Instruments of the study (problem solving test, creative thinking test, and mathematics appreciation scale) were administrated on the experimental and the control groups before and after the program. The researcher designed the developmental mathematics program after accessing internet sites and books related to the research topic, and administered the program using some effective teaching strategies (problem solving, mathematical communication, and realistic mathematics education). The researcher also designed the problem solving test, the creative thinking test, and the mathematics appreciation scale used as the instruments. The results indicated that there is a statistically significant difference between the mean scores of the control and experimental group students in the post application of the research instruments in favor of the experimental group. This signifies the effectiveness of the developmental mathematics program and its administration using some effective teaching strategies in developing the students' abilities regarding problem solving and creative thinking as well as in developing mathematics appreciation and the desire to continue studying mathematics for primary stage students.