For over a century, astronomers have been building physical models to study the internal structure of stars. These efforts have culminated in the so-called “standard stellar model”, the computational framework which defines much of the modern theory of stellar evolution stands. These models have been extremely successful at describing many observational properties of stars, including the intricate morphology of the color-magnitude diagrams of star clusters, the observed mass-radius relationship on the hydrogen-burning main sequence, and the detailed interior structure of the Sun.
Nonetheless, there remain several outstanding features of the galactic stellar pattern that our models fail to predict, and it is these discrepancies which point to interesting physical processes occurring in stars that have previously been neglected. In this talk, I will discuss some conspicuous failings of the standard picture of stellar evolution, and my efforts to reconcile theory with observations through the introducing of relevant but often ignored physical effects—including the structural and mixing effects of rotation and magnetic activity—into a modern stellar evolution code. I will show that such improvements can greatly improve the accuracy of certain model predictions, and hold important implications for the age scale of young stars and our ability to infer their fundamental parameters. I will also introduce a forthcoming set of public stellar models which incorporate the effects of magnetic starspots on the structure, evolution, and colors of solar-type stars.