Description:
These are the stairs outside one of the buildings at John Adams Middle School in Santa Monica, CA, where Winona Ryder stood at the end of Heathers, right before Christian Slater blew himself up and she lit her cigarette from the explosion. The red carpet on the stairs and red doors were obviously done for the film (as was the 'Westerberg' sign).
This wasn't the only school used for the whole film. Other high schools (and some interior sets) were used for exterior and interior school scenes.