Now more than ever, education leaders must focus strategically on educational technology professional development (ETPD) for teachers. Research evidence indicates that 30 hours of focused professional development is required to change teachers' professional practice. So despite positive opinions about the importance and efficacy of educational technology use, most teachers have not had sufficient time or opportunity to engage in the professional learning necessary to use educational technology effectively. In the first of a four-part series, the author describes a system for designing effective differentiated ETPD. (Contains 7 resources.) [For Part Two of this 4 part series, see EJ824510.]