The ability to think is a natural part of every human being and must be developed to its maximum potential. Consistent with educational reform efforts which emphasize the development of basic and complex thinking skills, this paper describes a model designed for curriculum planning which integrates ideas from critical thinking experts. The model's theoretical basis is built upon four different curriculum planning approaches: competency-based, ability-based, concept-based, and the Thinking Skills Model, each of which is described and explained as an aspect of the planning model as a whole. The model identifies the various essential elements of systematic curriculum planning, and the example used is a teacher competency chosen from the Teachers' Preparation Program of Cayey University College (Puerto Rico), a program with three main components: Educational Foundation, Methodology, and Practice Teaching. Once the competency and thinking skills are selected they become the basis for the elaboration of the other components of the model, which takes the required content across the curriculum and shows its depth and scope through three different levels of a student's cognitive and professional development: beginner, intermediate, and advanced. To illustrate the model, a topic and a teacher competence are presented in chart form and much of the text of this report is given over to a detailed explanation of each of the chart's 10 columns, or categories. A sample lesson is also provided. (LL)