With the national rollout of edTPA that champions language supports in content lessons, there is a renewed interest in academic language across disciplines and related pedagogy in the U.S. This study examines current knowledge of academic language demonstrated by teacher candidates at middle grades. An analysis (n = 42) of teacher candidates' lesson plans suggests that most teacher candidates associate academic language with content vocabulary only and are not prepared for planning mathematics instruction with academic language demands and supports. In particular, teacher candidates (1) were unfamiliar with the language function and how to conceptualize process and use of language in content lessons and (2) struggled to recognize the teacher's role to provide support for all students with differing language needs.