Assessment of student learning is integral to design of curricular experiences, a reality which is often purported to be more complex in online learning environments (Wijekumar, Ferguson & Wagoner, 2006) and characteristic of constructivist praxis (Comeaux, 2005-2006; Segall, et al., 2005). However, the framework within which evaluation occurs—with assessment as one form of evaluation, unique to the learning environment—is constant (Williams, 2004). Moreover, learning assessment was a meaningful topic pre-constructivism and assessment literature in online learning is nearly identical to that of assessment in general, especially as computerized assessment methods become more popular for all learners (Holtz & Radner, 2005; Robles & Braathen, 2002). There are differences and specific challenges; however, in practice those challenges need not be onerous. This chapter describes current practices in online learning assessment, notes similarities in on-site and online methods and explores the differences and how those differences are or can be addressed for online science learning.