As we have talked to people about this project, there has been interest in books and websites we have been referencing. This file will be updated periodically with references for the project. 

College Board report on results of AP Calculus exams:
https://research.collegeboard.org/programs/ap/data/participation/ap-2016

Characteristics of Successful Programs in College Calculus - Publications & Reports, Math Association of American
http://www.maa.org/programs/faculty-and-departments/curriculum-development-resources/national-studies-college-calculus/cspcc-publications

National Academy of Sciences report on barriers and opportunities on 2- and 4-year STEM degrees:
https://www.nap.edu/catalog/21739/barriers-and-opportunities-for-2-year-and-4-year-stem-degrees

Our books, 3D Printed Science Projects (first volume)
http://www.apress.com/us/book/9781484213247

and Volume 2: 
http://www.apress.com/us/book/9781484226940

Principia, photographs of Newton’s copy
https://cudl.lib.cam.ac.uk/view/PR-ADV-B-00039-00001/757

Definitive translation with commentary:
https://www.amazon.com/Principia-Authoritative-Translation-Mathematical-Principles/dp/0520290887

Jo Boaler, Mathematical Mindsets
https://www.amazon.com/Mathematical-Mindsets-Unleashing-Potential-Innovative/dp/0470894520

Calculus Made Easy Revised, Updated, Expanded Edition
In print since 1910
by Silvanus P. Thompson (Author), Martin Gardner (Author) 
https://www.amazon.com/Calculus-Made-Easy-Silvanus-Thompson/dp/0312185480