Stasera voglio ripassare la lezione di matematica con calma.

Yes. Stasera is a very common shortened form of questa sera, and both mean this evening / tonight.

• Stasera = more compact and very natural in everyday speech
• Questa sera = also correct, sometimes a little more explicit or slightly more formal

So:

• Stasera voglio ripassare...
• Questa sera voglio ripassare...

Both are correct.

Italian often leaves out subject pronouns when they are already clear from the verb form.

Here, voglio means I want, so io is not necessary.

• (Io) voglio = I want

Including io is possible, but it usually adds emphasis, contrast, or clarity:

• Io voglio ripassare = I want to review / As for me, I want to review

In a neutral sentence, leaving it out is more natural.

Because with volere (to want), Italian normally uses the verb directly with an infinitive, with no preposition in between.

Pattern:

• volere + infinitive

Examples:

• Voglio mangiare = I want to eat
• Vuoi uscire? = Do you want to go out?
• Vogliamo studiare = We want to study

So:

• voglio ripassare = I want to review

Using di here would be incorrect.

Not exactly.

• studiare = to study
• ripassare = to review, to go over again

So ripassare suggests that the person has already studied the material before and now wants to revise it.

For example:

• Devo studiare matematica = I need to study math
• Devo ripassare matematica = I need to review math

In your sentence, ripassare la lezione di matematica means reviewing that math lesson again.

Di matematica means of math or, more naturally in English, math as the subject.

So:

• la lezione di matematica = the math lesson

Italian often uses di + subject to specify what kind of lesson, book, teacher, etc.

Examples:

• professore di italiano = Italian teacher
• libro di storia = history book
• lezione di matematica = math lesson

Here, di matematica tells you what subject the lesson is about.

It is singular because the speaker is talking about one lesson.

• la lezione = the lesson
• le lezioni = the lessons

If you wanted to say the math lessons, you would say:

• le lezioni di matematica

So the original sentence specifically refers to one lesson to review.

Italian uses definite articles more often than English does.

Here, la lezione means the lesson, referring to a specific lesson that the speaker has in mind. In many cases, Italian sounds more natural with the article where English might be more flexible.

Compare:

• Voglio ripassare la lezione di matematica = I want to review the math lesson
• Voglio ripassare una lezione di matematica = I want to review a math lesson

Without an article, this phrase would generally not sound correct here.

Con calma literally means with calm, but in natural English it usually means:

• calmly
• without rushing
• at an unhurried pace
• taking my time

So in this sentence, it means the speaker wants to review the lesson in a relaxed, careful way, not quickly or under pressure.

You can hear con calma in many everyday situations:

• Parliamone con calma = Let’s talk about it calmly
• Lo faccio con calma = I’ll do it without rushing

Because it works naturally there as an adverbial phrase describing how the action is done.

The sentence structure is:

• Stasera = time
• voglio ripassare = main verb idea
• la lezione di matematica = object
• con calma = manner

So the sentence flows as: Tonight I want to review the math lesson calmly / without rushing.

Italian word order is fairly flexible, but this order is very natural. You could move con calma earlier for emphasis, but the original version is the most neutral.

Yes, voglio is present tense: I want.

Italian, like English, often uses the present tense to talk about a current intention that refers to the near future.

So:

• Stasera voglio ripassare... literally = Tonight I want to review...
• In context, it also implies a plan or intention for tonight

This is completely normal. Italian does not need a special future form here.

You could also use the future in some contexts, but it would change the tone:

• Stasera ripasserò la lezione di matematica = Tonight I will review the math lesson

That sounds more like a firm statement about what will happen, while voglio ripassare emphasizes desire or intention.

The word order is not completely fixed, but the original order is very natural.

Original:

• Stasera voglio ripassare la lezione di matematica con calma.

Possible variations:

• Voglio ripassare la lezione di matematica con calma stasera.
• La lezione di matematica voglio ripassarla con calma stasera.

These are grammatically possible, but they change the emphasis and may sound less neutral.

For a learner, the original sentence is the safest and most natural everyday order: time + verb + object + manner.

Yes, in this sentence matematica appears without an article because it is the name of a school subject after di.

So:

• lezione di matematica
• professore di matematica
• compito di matematica

This is normal.

If you were talking about mathematics in a more general or abstract sense, an article might appear in other structures, but in school-subject expressions like this, no article is usually used.