Here are some online places to begin:
Arlyn Freed's ESL/EFL English for Specific Purposes
Comments/suggestions should be sent to: firstname.lastname@example.org ... NetStoreUSA (books on medical topics) ... English for Science and Technology Online ...
Science English Book,Dictionary Books for Scientists,ESL Students ...
Science English Book,Dictionary Books for Scientists,ESL Students,Terms,Vocabulary Exercises Audio CD Workbook.
And then here are many sources for using after students have their "English science" vocabulary built up a bit.
I'll keep looking.