This paper, designed to assess the degree of implementation of the important features of a curriculum innovation, was presented at the 1978 Bat-Sheva Seminar on Curriculum Implementation and its Relationship to Curriculum Development in Science, Rehovot-Jerusalem, Israel. It investigates the use of sub-interviews within the main interview to assess the level of use of each of the components of interest innovation bundle. The methodology described is used to measure the level of implementation of the junior high school science program, The National World (TNW). This is the revision and modular adaptation of the Intermediate Science Curriculum Study (ISCS). A total of five teachers using the TNW program were interviewed personally or by telephone. Results show that all teachers are regular users of the program and there are considerable variations in their degree and level use of the program. Scales used to measure the use of innovation and interview format are also presented. (HM)