Learn Spanish (Latin America): El profesor está en la escuela ahora.

We use está (from the verb estar) because we are talking about a location. In Spanish, you always use estar to say where someone or something is located, whether they are there temporarily or permanently.

Why is there an accent mark on the "a" in está?

The accent mark tells you to put the stress on the last syllable when speaking. It is also crucial because without the accent mark, esta is a completely different word meaning "this" (as in esta escuela, meaning "this school").

Does en mean "in" or "at"?

It translates to both! The Spanish word en is very flexible and can mean "in", "on", or "at" depending on the context. In this sentence, en la escuela can naturally translate to "in the school" or "at school".

Why do we need la before escuela? In English, we usually just say "at school".

In Spanish, general locations and institutions almost always need a definite article (like el or la) when they follow a preposition like en. So instead of saying just en escuela, you must say en la escuela.