The aim of this paper is to discuss the role of coding and observation manuals in classroom studies. While observation manuals have been a part of the methodological toolkit for measuring various aspects of instruction for decades, the field has also been suffering from "paradigm wars," fragmentation and local production of instruments. Common frameworks for investigating teaching are needed, including observation instruments for teaching that are both generic and subject specific. Such common tools for research developed within an integrated methodological design could help researchers make progress in aggregating knowledge about the impact of different teaching approaches across settings and subjects. This article serves as one such integrative mechanism by summarizing and reviewing existing manuals targeted towards developing knowledge for and in teaching. The analysis provides status, overview and focus of the different observation manuals; additionally, the article discusses how recent developments in instruments and coding procedures might provide increased rigour and a shared vocabulary to talk about teaching. We discuss both pitfalls and possibilities of coding manuals, and argue that if used in a reflexive manner, coding manuals can provide a common language and vocabulary when talking about--and researching--classroom teaching and learning.