The importance of having a highly qualified teacher in every classroom is an educational necessity. Determining which teacher characteristics define teacher quality and measuring their impact on student outcomes has offered mixed results. This study explored the effect of teachers' knowledge of language and literacy on their students' reading outcomes in foundational skills and reading comprehension. Data from 9,640 students and 512 classroom teachers in 112 schools were analyzed using multi-level mixed effects modeling to account for the nested data. After controlling for student and teacher-level variables, results showed that teachers' knowledge of language and literacy reliably predicted students' spring foundational skills scores, but not reading comprehension scores. These findings support the idea that more knowledgeable teachers generate students with more favorable reading outcomes. Implications are discussed in addition to directions for future research.