Deepening Students’ Understanding of Algorithms: Eﬀects of Problem Context and Feedback Regarding Algorithmic Abstraction Leigh Ann Sudol June 2011 School of Computer Science Carnegie Mellon University Pittsburgh, PA 15213 Thesis Committee: Mark Stehlik, Co-Chair Sharon Carver, Co-Chair Ken Koedinger Frank Pfenning Carsten Schulte Submitted in partial fulﬁllment of the requirements for the degree of Doctor of Philosophy. Copyright c  2011 Leigh Ann Sudol