I am required to be certified at the highest level for my position. Must I first obtain certification at the lower level?

NO. You only need to obtain the highest level certification. However, keep in mind that many of the courses required for the highest certification require completion of lower level prerequisite courses. You must complete the prerequisite courses but you are not required to actually obtain the certification at the lower levels. The certification requirements and the prerequisites for each course can be found in the DAU Interactive Catalog at https://icatalog.dau.edu/onlinecatalog/tabnavlas.aspx