The purpose of this research is to better understand the uses and potential of triadic dialogue (initiation-response-feedback) as a dominant discourse pattern in test-driven environments. We used a Bakhtinian dialogic perspective to analyze interactions among high-stakes tests and triadic dialogue. Specifically, the study investigated (a) the global influence of high-stakes tests on knowledge types and cognitive processes presented and elicited by the science teacher in triadic dialogue and (b) the teacher's meaning making of her discourse patterns. The classroom talk occurred in a classroom where the teacher tried to balance conceptual learning with helping low-income public school students pass the national tests. Videos and transcripts of 20 grade 8 and 9 physical science sessions were analyzed qualitatively. Teacher utterances were categorized in terms of science knowledge types and cognitive processes. Explicitness and directionality of shifts among different knowledge types were analyzed. It was found that shifts between factual/conceptual/procedural-algorithmic and procedural inquiry were mostly dialectical and implicit, and dominated the body of concept development lessons. These shifts called for medium-level cognitive processes. Shifts between the different knowledge types and procedural-testing were more explicit and occurred mostly at the end of lessons. Moreover, the science teacher's focus on success and high expectations, her explicitness in dealing with high-stakes tests, and the relaxed atmosphere she created built a constructive partnership with the students toward a common goal of "cracking the test." We discuss findings from a Bakhtinian dialogic perspective and the potential of triadic dialogue for teachers negotiating multiple goals and commitments.