In my experience, I’ve come across different textbooks for different languages, and I think there are some basic criteria that a good textbook needs to follow. These requirements are what I’m going to address in this post. Having written a language learning guide myself, and being a student who uses textbooks frequently, I should be able to cover this topic pretty adequately. Hopefully, you can use this list to assess whether a book is good enough for you, or if you’re writing one yourself!
1) Consider the audience of the book when writing it and assess the language when reading it. If the book in question is an AP or college-level book, chances are that it uses more technical language and goes more in-depth on certain topics. For example, in my Spanish class, we use Encuentros Maravillosos from Prentice Hall, by Abby Kanter, to cover Spanish literature at basic level, before going on to the AP level. The audience here is almost exclusively made up of high school students, as the language of the book is meant to prepare the student for an AP or college-level course. On the other hand, the Realidades series, which I had used in all my Spanish classes up until Spanish III, is oversimplified sometimes. There is a Realidades 4, but it is not considered good enough for a high school honors class. The language aims more at a younger class range, using largely nontechnical language, so as not to confuse learners who may not be able to understand higher level texts. For a non-school example, Complete Catalan: A Teach Yourself Guide, by Anna Poch Gasau and Alan Yates, I feel, is written almost exclusively in technical language. While I understand some amount of the technical language, it seems that this book is aimed at a wide audience, which may not include linguists or language-obsessed people such as me, who know what open and closed vowels are. The commonly used version of the preterite tense is called periphrastic! While this may be true, you can’t expect that the average person will know what that means, as it’s not even relevant for the purposes of the book. I also feel that it is kind of pompous in phrasing anyway, which is not good for helping people learn. Basically, a book can’t be too simple and can’t be too complex, otherwise the average audience isn’t going to get it. This tends to be a matter of preference when it comes to learning, because some people learn more with all the technical talk, but overall, the best approach is the semi-technical form.
2) What is the purpose of the book? Textbooks can vary in purpose from curriculum-based learning to learn new skills, to practicing current ones, to reviewing. A book focused on practice is basically a workbook or collection of readings and/or dialogues to use skills in context. A review textbook is a book that covers all the material that you should have learned to that point, to some standard, and the book may even be written entirely in the target language to facilitate review. Choose the way a book is structured wisely, depending on how you (the writer) want it to be used, or how you (the reader) want to learn, or what you need the book for. For example, Con Fantasia by Marcel Danesi, Michael Lettieri, and Salvatore Bancheri, is an AP-level review book for Italian. The book is written mostly in Italian, because it’s aimed at helping AP-level Italian students review material for the AP Exam, featuring comprehensive reviews of grammar, conventions, vocabulary, and idioms, and also has some readings for the student to use, as well as being accompanied by a workbook.
3) The text is organized meaningfully. When you’re learning a language, you should be learning vocabulary and grammar in a constructive manner, preferably in the way of themes. For example, if you’re learning vocabulary about vacationing and leisure time, that would be a good time to introduce the past tense(s). When you’re discussing purchases and sales, you should include info about structures concerning such things. Vocabulary, especially, needs to be organized in a pertinent way. Vocabulary should be related when given in lists. I can’t express how important this is, especially after starting to use Complete Catalan, which has the most disorganized vocabulary lists I’ve ever seen. They didn’t even bother to group words by topic, part of speech, or anything. So, organization is important!
I may or may not add some more to this post, but for now, this is my piece on this topic. Feel free to leave your comments!