In this essay I elaborate on three ideas that emerged from reading the work of Sylvie Barma. These points are in response to curriculum reform and the use of activity theory: (a) curriculum reform as a public policy; (b) a reflection about the process followed by teacher implementation of that reform in a biology classroom; and (c) the sense of experience as an objective anchored in activity theory. This commentary deals with several entanglements of science teaching and learning where I am also able to address some of my own queries in the use of activity theory in research.