Learn Spanish (Spain): Estimada directora: Mi hijo no irá al colegio mañana. - Dear Principal: My son won't go to school tomorrow.

In Spanish, formal letters and emails always use a colon after the opening greeting. Using a comma here, like we often do in English, is actually considered incorrect in Spanish writing conventions.

Why use Estimada for "Dear" instead of Querida?

Estimada is used for formal or professional correspondence. Querida is also translated as "Dear", but it is reserved for friends, family, and loved ones. Since this is a formal note to a school principal, Estimada is the correct choice, and it ends in "-a" to match the feminine noun directora.

Does colegio mean the son is going to college (university)?

No, colegio is a classic "false friend." It refers to a primary or secondary school, not a university. If the son were going to university, you would use the word universidad.

Could I say no va a ir instead of no irá here?

Yes, you absolutely could. No va a ir (he is not going to go) is extremely common in everyday Spanish. However, irá (the simple future tense) is slightly more formal and concise, which fits the professional tone of a written absence note perfectly.