Without a doubt, teaching writing at any level in any language is challenging. A primary reason for the difficulty is that most students want to SPEAK (not "write") English. The students that I've encountered over the years find writing a pain in the.... neck but a necessary pain to get admission into a university program or a high score on a language exam (e.g., iBT TOEFL, IELTS, FCE/CAE/CPE).
With low-intermediate-level students, my job is to get them to write and control different kinds of sentence structures (simple, compound, and complex) and to organize those into one well-organized, coherent paragraph. I've examined many ESL textbooks on writing, hoping that one of them contains another way to look at what I do. Thus, I was pleased to run across an article in Slate about "How to Write a Good Sentence."
Having grown up with W. Strunk, Jr. and E. B. White's Elements of Style as the last word on good sentence structure and not liked what it did to my creative side and love of the sound of words, I enjoyed having someone put the latter little tome into a historical perspective. I felt less burdened recently telling my students that "Rewriting means rethinking."
Even if I don't offer them an alternative word, I encourage them to always make an effort to use more colorful language or more varied structures in their writing. I ask them to avoid the two-cent words (good, bad, thing...) and to use some five dollar words (extraordinary, disgusting, item...). Alternate a short simple sentence with a ten-word complex sentence. Read the sentence aloud. How does it sound? Language evolved as a spoken means of communication - later people created the symbols for words. Writing does connect to speech - but this is what Strunk and White forgot to stress in their guide. Language is spoken. To get good at writing (and speaking) - to be eloquent, you should be encouraged to be more than sparing - especially in the beginning. Have fun expressing yourself!