RFC: Replacing the current Calculus and Differential Equations courses with proof based versions

Problem:
The current Calculus 1, 2, 3, and Differential Equations courses in the OSSU math roadmap focus too much on doing calculations instead of teaching proofs.

Duration:
This should most often be 1 month from the date of posting.

Background:
Right now, the calculus and differential equations courses are set up in a way that works best for engineering students. They focus on using theorems to solve problems by calculation.
However, students who want to study math as a major need courses that help them learn how to build rigorous proofs and think abstractly (yes, even if those courses are first year courses. Take for example this math curriculum from the University of Toronto, they start with a proof based course in Linear Algebra their first year)
In short, while the current courses are good for computation, they don’t match what a top pure math (even applied math if we take the University of Toronto as an example) curriculum should provide.

Proposal:

• Replace the current Calculus courses with Calculus with Theory and Multivariable Calculus with Theory from MIT Open Courseware.
• Make Calculus 1A: Differentiation, Calculus 1B: Integration and Calculus 1C: Coordinate Systems & Infinite Series part of high school math and prerequisites for Calculus with Theory.
• Swap out the Differential Equations course with Honors Differential Equations.

Alternatives:

• Keep the current computational courses for those interested in it, but create a separate track with proof-based courses for people pursuing a pure math major roadmap.

Review the current Calculus 1–3 and Differential Equations entries in the math roadmap, then compare them with the linked MIT course descriptions. Determine whether the proposed proof-based replacements or a separate track fit the roadmap, and document the agreed course sequence and prerequisites as the completion criteria.