Hi Susan!

Sunspots (and solar magnetic field in general) are generated deep in the Sun in the so-called convection zone by turbulent plasma motions and associated electric currents. The Sun's uneven rotation (faster at the equator than at the poles) wraps the magnetic field lines around the Sun. The field lines form magnetic tubes that rise to the surface of the Sun and poke through as loop-like arcs. The regions where strong magnetic field in these tubes goes in and out from the Sun are seen as sunspots. They appear dark because strong magnetic field prevents hot gas rising to the surface and therefore they are cooler than their surroundings.

Emilia