Here are selected resources from the Differential Equations course I sometimes teach.
Introduction to the course
Introduction to differential equations
Numerical solutions
First order equations
Complex numbers
Linear equations with constant coefficients: homogeneous
Linear equations with constant coefficients: inhomogeneous
Power series solutions
Introduction to dynamical systems
Advanced 1-d flows
Dimensional analysis
Nondimensionalization
Bifurcations of dynamical systems
Linear algebra review
Solving systems of linear ODEs
Linear dynamical systems
Nonlinear dynamical systems
Conservative systems
Chaos