In this paper the nature of learning progressions and related concepts are discussed. The notions of learning progressions and learning trajectories are conceptualized and their usage is illustrated with the help of examples. In particular the nuances of instructional interventions utilizing these concepts are also discussed with implications for the teaching and learning of mathematics.
Battista, Michael T.
"Conceptualizations and Issues related to Learning Progressions, Learning Trajectories, and Levels of Sophistication,"
The Mathematics Enthusiast: Vol. 8
, Article 5.
Available at: http://scholarworks.umt.edu/tme/vol8/iss3/5