Directed Discourse Approach to Science Instruction
The Directed Discourse Approach to Science Instruction (D.D.A.S.I.) assists students in appropriating science discourse in the explanation and discussion of science phenomenon. The D.D.A.S.I. is a four-stage pedagogical approach to science teaching that strengthens the use of scientific discourse by explicitly scaffolding students’ use of science language. The D.D.A.S.I. seeks to provide students with a conceptual and linguistic repertoire that will promote their scientific literacy development.
Stage one, the Pre-Assessment Instruction phase, involves employing a query-oriented approach to introducing the primary ideas of the concept. This stage of the instruction involves the teacher’s pre-assessment of students’ ideas regarding the topic free from the use of academic discourse. This phase is designed with two purpose in mind: 1) To allow students to identify their understanding of the phenomenon being discussed. 2) To allow the teacher to understand what students’ preconceptions of the concept, while addressing many of the misconceptions students bring to the classroom. For example, a teacher could conduct a pre-assessment regarding photosynthesis by asking: What do plants need to grow?.
Stage two is the Content Construction Phase. In this phase, the teacher introduces the correct versions of the content discussed in stage 1, without providing the detailed language and overbearing technical descriptions associated with science. This stage involves engaging students in activities that will introduce the basic ideas associated with the topic without use of detailed science language. Following the example above, the teacher can discuss the role of air, sunlight, and water, while addressing the misconception that plants need dirt to grow (diagrams and experiments can provide an inquiry approach to this stage).
In stage three, the Introduction of Explicit Discourse Phase, the teacher scaffolds students’ use of specific science discourse by requiring the students to use scientific genre for classroom writing and talk. In this stage, generic terms like air, sunlight, and water can be replaced with scientific terms like carbon dioxide, photons, and H20.
In the final stage, the Scaffolding Opportunities for Discourse Phase, the teacher provides students with several opportunities to articulate their understanding of the phenomenon being explored in the lesson. This final stage uses assessment activities to allow the students to write about and explain the concepts being discussed using the technical discourse of science, without the assistance of the teacher. For example, assessment activities may ask questions like: Please describe how lilies engage in photosynthesis, in your description use words like photon, carbon dioxide, and H20.