Learn Hardcore Spanish (Latin America): Estoy solo en la escuela.

We use estar because it describes a temporary or changeable condition (being alone at this specific moment), rather than a permanent characteristic. Ser would imply a more permanent or inherent state, which doesn’t fit here.

Why is it "solo" instead of "sola"?

If the speaker identifies as male, they use solo. If it’s a female speaker, then she would say sola. This adjective must match the gender of the speaker.

Why do we say "en la escuela" and not "a la escuela"?

We say en la escuela to indicate a location. If you were talking about going or traveling to school, you might use a la escuela (for example, Voy a la escuela), but with estar, the correct preposition is en.

Is there a difference between "solo" and "sólo"?

Historically, sólo (accented) meant "only," and solo (without an accent) meant "alone." Modern Spanish grammar rules generally no longer require the accent on solo, so context tells you whether it means "alone" or "only."

Is "escuela" the same as "colegio" or "instituto"?

In many parts of Latin America, escuela can be used generally for "school," while colegio often refers to private or secondary schools. Instituto is sometimes used for specialized or vocational schools. Usage varies by region, but escuela is a very broad term that usually works fine for any school context.