There is a textbook for this course, which is Jürgen M. Meisel (2011), First and Second Language Acquisition, Cambridge University Press. The BU bookstore should have copies, or you can acquire it on Amazon or elsewhere.

Note that there is a Kindle edition (as well as an electronic edition from CUP), and at least right now the Kindle edition is significantly cheaper, so it’s worth considering that as an option.