The purpose of the study was to examine how disciplinary literacy instruction influenced the quality of science informational text produced by second-grade students (N = 45) using the compare/contrast and the sequence text structures. The instruction took place over eight weeks with two four-week units, and with three 30-minute lessons provided weekly. A Wilcoxon Signed-Rank Test was used to compare pre/post instruction writing samples because these data were ordinal. Results revealed that after the disciplinary literacy instruction students were able to produce higher quality texts, but only consistently in the areas of providing science facts and definitions and using ending punctuation in sentences. Finally a t-test was used to compare student writing based on text structure being used. Findings revealed that students were able to produce higher quality informational text when the sequence text structure was used compared to when students used the compare and contrast structure.