Koreans understandably have a hard time learning to use the articles "a" and "the" because they
don't exist in the Korean language. -- and probably not in many other languages. Yet many books
sold in Korea, including the old Interchange book I just looked at, typically give a picture of an
object like "skirt" and -- you guessed it (perhaps) -- they fail to put "a" before the word even though
it would probably rarely cause the publisher/author to need extra space on the page. They sell their books
in Korea without regard for the learning needs of Koreans. If you ask a Korean looking at the picture,
why should (s)he say "It's a skirt" in answer to the question, "What is it?" They usually say, "It's skirt."
Unfortunately, even the Korean middle school books are usually guilty of the same folly.

Every time I see a picture which is identified in English without the appropriate "a(n)" or "the," I tell my
students to write the article in their books.

I have already tried to post a Tic Tac Toe game twice in good faith, but the attachment appears to be inaccessible.
Yes, I want to post at least 5 times and be able to download materials, so this time I posted something without an attachment. I will post the Tic Tac Toe game again, and other lesson plans, when I know why my attachments can't be opened.

Yet many books sold in Korea, including the old Interchange book I just looked at, typically give a picture of an object like "skirt" and -- you guessed it (perhaps) -- they fail to put "a" before the word

I keep arguing for printing articles in learning materials and include them when I make my own. When we study French, everything has an article because we have to learn whether to use the masculine or feminine article.  In English, Korean learners need to first learn to use an article at all.  The a/the divide is ridiculously hard for non-native-speakers to master, but picking up on "a skirt" instead of "skirt" is doable.  It would be lovely if the professional materials would put them in. 

I tend to use the indefinite article in English, since I find they are used most often in the context of what our students are learning, but I use "the" for things that we most commonly say "the" with, like "the store."  ("I must go to the store" or "I went to the store" are more common in our lessons than "my father owns a store.")  What do you recommend using?  Also, for non-countable nouns, would you suggest just printing the noun, or printing the word "some" with things like noncountable foods (as they learn in "Do you want some more?" and "Can I have some water?"). 

Koreans understandably have a hard time learning to use the articles "a" and "the" because they
don't exist in the Korean language. -- and probably not in many other languages. Yet many books
sold in Korea, including the old Interchange book I just looked at, typically give a picture of an
object like "skirt" and -- you guessed it (perhaps) -- they fail to put "a" before the word even though
it would probably rarely cause the publisher/author to need extra space on the page. They sell their books
in Korea without regard for the learning needs of Koreans. If you ask a Korean looking at the picture,
why should (s)he say "It's a skirt" in answer to the question, "What is it?" They usually say, "It's skirt."
Unfortunately, even the Korean middle school books are usually guilty of the same folly.

Every time I see a picture which is identified in English without the appropriate "a(n)" or "the," I tell my
students to write the article in their books.

I have already tried to post a Tic Tac Toe game twice in good faith, but the attachment appears to be inaccessible.
Yes, I want to post at least 5 times and be able to download materials, so this time I posted something without an attachment. I will post the Tic Tac Toe game again, and other lesson plans, when I know why my attachments can't be opened.

The words "one", "a" and "an" historically come from the same root word.

http://dictionary.reference.com/browse/an

___
Origin:
before 950; Middle English; Old English ān one  in a weakened sense

an
indefinite article, 12c., from O.E. an  (with a long vowel) "one, lone," also used as a prefix an-  "single, lone;" see one for the divergence of that word from this. Also see a,  of which this is the older, fuller form. In other European languages, identity between indefinite article and the word for "one" remains explicit (e.g. Fr. un , Ger. ein , etc.) O.E. got by without indefinite articles: He was a good man  in O.E. was he wæs god man.  Circa 15c., a  and an  commonly were written as one word with the following noun, which contributed to the confusion over how such words as newt  and umpire  ought to be divided (see N). In Shakespeare, etc., an  sometimes is a contraction of as if  (a usage first attested c.1300), especially before it.
___

So in many cases, if you want to see if "a" or "an" is appropriate to use in a certain situation, try using the word "one" instead.   For example:

1)  ___  skirt  ->  one skirt ->  okay so "a skirt" is okay
2)  ___  milk  ->  one milk  ->  sort of weird, so "a milk" is not okay.

I'm sure you can think of many other examples.

Picked this up on a different thread, but I think the grammatical explanations on this thread are worth reviewing.

This is a ppt from another teacher to which I've added some pictures and hyperlinks.  The bucket is my gimmick for teaching countable/uncountable nouns.

Wow this is a terribly old thread but I think the reason the books don't always add the article because that teaches the students that it's always going to be there, which it's not. Sure "it's a skirt" but what happens when "it's your skirt"? Suddenly you'll hear "It's your a skirt." Something's not quite right about that. I'm not a stickler for articles when I'm free-talking with students but if they're doing textbook sentence drills they better remember them. Of course when we're repeating the sentences we should use them and drill them so the students remember and hopefully the articles will be remembered later, but when it comes to actual conversations there's no point in correcting every article mistake your students make, that'll just mean they don't want to talk to you from fear of making mistakes.