We conducted a field-study over ten weeks, where 29 undergraduate and graduate students collaboratively summarized two data science textbooks and some recent research papers. They created 934 nodes. Of these, 573 were leaf nodes with no children; among non-leaf nodes, on average each was identified as a prerequisite of 2.66 other nodes. Students submitted a total of 2,131 proposals, including 721 for edits to nodes and 1,410 for revisions to links.