Vou esperar até que a aula acabe para falar com a professora.

Vou esperar is the very common ir + infinitive future construction.

• vou = I go / I am going
• esperar = to wait

So literally it looks like I am going to wait, but in normal English it often just means I will wait.

In European Portuguese, this is a very natural everyday way to talk about the future. It usually sounds more conversational than the simple future form esperarei.

Yes. Esperarei até que a aula acabe para falar com a professora is grammatical.

The difference is mostly about style:

• vou esperar = more common in everyday speech
• esperarei = a bit more formal, written, or emphatic

A native speaker would very often choose vou esperar in normal conversation.

Because até que introduces a whole clause with its own verb:

• até que a aula acabe

Here, a aula acabe is a full clause, so que is needed.

Compare:

• até ao fim da aula = until the end of the class
  
  • noun phrase
• até que a aula acabe = until the class ends
  
  • full clause with a verb

So até by itself often comes before a noun or noun phrase, while até que introduces a verb clause.

Because after até que, when the action is still in the future or has not happened yet, Portuguese uses the present subjunctive.

So:

• acabe = present subjunctive of acabar
• acaba = present indicative

In this sentence, the class has not ended yet. The speaker is waiting for that future event to happen, so acabe is the correct form.

This is one of those places where Portuguese makes a distinction that English usually does not.

Acabe is the present subjunctive form of acabar for a aula (third person singular).

The full idea is:

• até que a aula acabe = until the class ends

Here, a aula is the subject, so the verb must match it:

• a aula acabe
• not a aula acabem

So even though acabe may look unusual at first, it is just the normal subjunctive form required by the structure.

Yes — and that is also very natural.

So these are both good:

• até que a aula acabe
• até a aula acabar

The difference is mainly stylistic:

• até que a aula acabe = a bit more explicit, with a fully conjugated clause
• até a aula acabar = more compact, often very natural in speech

As a learner, it is useful to recognize both patterns.

Because para + infinitive is the normal way to express purpose when that structure is enough.

• para falar com a professora = in order to talk to the teacher

You could say para que eu fale com a professora, but that sounds heavier and more explicit. It is not wrong, just less natural here.

A good rule of thumb:

• para + infinitive = usually the simplest, most natural option
• para que + subjunctive = more explicit, often used when needed for clarity or style

Falar com is very common and usually suggests talking with someone — a normal interaction or conversation.

• falar com a professora = talk to / talk with the teacher

Falar a or falar a alguém can also exist, but it often sounds more formal, literary, or more one-directional, like speak to rather than have a conversation with.

In everyday Portuguese, falar com is usually the most natural choice here.

Because Portuguese uses definite articles very naturally with nouns where English may or may not use them.

Here:

• a aula = the class
• a professora = the teacher

These are specific, identifiable things in the situation, so the article is expected.

For English speakers, this is worth noticing because Portuguese often uses articles more regularly than English does.

Yes, to some extent.

The original order is very natural:

• Vou esperar até que a aula acabe para falar com a professora.

You could also say:

• Para falar com a professora, vou esperar até que a aula acabe.

That is still correct, but it gives a little more emphasis to the purpose.

The original version is probably the most neutral and natural for everyday use.

Yes. Até que a aula termine is also correct.

Both acabar and terminar can mean to end / to finish in this context.

Very roughly:

• acabar = very common, everyday
• terminar = also common, sometimes felt as slightly more formal or neat, depending on context

In this sentence, both work well:

• até que a aula acabe
• até que a aula termine

A native speaker would understand either without any problem.