I'd rather use EFL than ESL, though that's the term used in this presentation. However, for my students and for me as well, English is a foreign language, never a second one.

Let's talk grammar!

Here you can see a very neat and clean presentation on tenses. I hope you find it of some interest for your classes anyway.

Besides, you can also read free articles at Eli Hinkel's webpage. I copy from her site:

Eli Hinkel has taught ESL and applied linguistics, as well as trained teachers, for over twenty five years and has published numerous books and articles on learning second culture, and second language grammar, writing, and pragmatics in such journals as TESOL Quarterly, Applied Linguistics, Journal of Pragmatics, and Applied Language Learning. She is also the editor of the Routledge ESL & Applied Linguistics Professional Series of books and textbooks for teachers and graduate students.

Right, that's all for now.

Enjoy life!