Remnant and Renewal by Mitch Glaser and Alan Shore tells the story of the Jewish people from the former Soviet Union, as well as those who have sought to bring the Gospel to them. What the Rabbonim Say About Moshiach, by Douglas Pyle, goes through principal rabbinic texts that have been traditionally and historically understood to be in reference to the Messiah. Both of these books are great resources for students looking to reach their Jewish friends for Messiah.