This study examined the ability of teachers to produce grammatical manual representations of English under normal classroom conditions. Three groups of teachers—inexperienced signing hearing teachers, experienced signing hearing teachers, and deaf teachers—were observed three times using a live-observation system. Twenty-three teachers were observed with an inter-coder reliability of .896. Differences in teachers' ability to use separate signs for English grammatical endings and the use of ASL-like signing were found.
The general conclusion of the study is that increased experience leads to increased use of natural language features in classroom communication.