From our own experience, students of Arabic—particularly spoken Arabics—suffer greatly from a lack of reference materials.
We wrote Syrian Colloquial Arabic to help.
The material was trialled with students at the British Council in Damascus in 1997 and self-published on a very low budget. Find out more about the authors.
Our aim was to write the textbook we wished we'd had when we were learning Arabic. We wanted something that gave the student immediately useful, practical language (for living, shopping, getting around, etc) while giving a systematic explanation of the grammar.
We wanted to avoid sterile and unrealistic examples or texts artificially constructed to illustrate grammatical points, as well as avoid the "phrase book approach" of many colloquial language texts, which essentially list phrases and idioms, and explain how to use them, but don't go into the grammar in a systematic way.
The other main idea (and this is peculiar to Arabic, so may not be classifiable under generic language-teaching methodologies) was to set out the Syrian colloquial language in a way that could be linked to Modern Standard Arabic.
The original, ambitious and now abandoned, plan was to develop a similar book on MSA (and eventually on other Arabic colloquials), with each chapter of each book dealing with the corresponding vocabulary and grammar of each dialect.
In this way, a student learning, say, both Syrian and MSA could readily identify the common points and understand the differences, and get a much better feel, much more quickly, for how the colloquial and formal languages work and fit together.
Sadly, the other books remain just a bold idea, but the way the grammar is developed in the Syrian book was very carefully designed in order to be compatible with a similar exposition of MSA grammar.