onazi kyoukasyo wo tukatte mo, hito ni yotte kangaekata ha tigaimasu.

使っても is the pattern Vて + も, which often means:

• even if ...
• even though ...
• although ...

So:

• 使う = to use
• 使って = te-form of 使う
• 使っても = even if/though (someone) uses

In this sentence, it connects to the next idea:

• 同じ教科書を使っても、...違います
• Even if they use the same textbook, ... things are different

The nuance is concessive: you might expect the same textbook to lead to the same result, but that is not necessarily true.

同じ is a special word. It can directly modify a noun:

• 同じ教科書 = the same textbook
• 同じ人 = the same person
• 同じ考え = the same idea

You do not use な here:

• natural: 同じ教科書
• unnatural: 同じな教科書

You also do not need の in this structure.

So 同じ behaves a little unusually compared with regular な-adjectives.

Because 教科書 is the direct object of 使う.

• 教科書を使う = to use a textbook

Even though 使っても is part of a larger sentence, it still keeps its normal object marker:

• 同じ教科書を使っても = even if/though (someone) uses the same textbook

So the structure is still:

• object + を
  • verb

人によって means depending on the person or from person to person.

This is the pattern:

• Nによって = depending on N / according to N / varying by N

So:

• 人によって = depending on the person
• 国によって = depending on the country
• 場合によって = depending on the situation

In this sentence, it means that the difference comes from the individual person:

• 人によって考え方は違います
• Ways of thinking differ from person to person

They are very different.

によって

Means:

• depending on
• by
• according to
• due to

Example in this sentence:

• 人によって違います
• It differs depending on the person

にとって

Means:

• for
• to
• from the viewpoint of

Example:

• 私にとって難しい
• It is difficult for me

So in this sentence, 人によって is correct because the meaning is variation by person, not from the perspective of a person.

考え方 literally means way of thinking.

It is made from:

• 考え = the stem of 考える (to think)
• 方 = way/method of doing something

So this pattern often creates words meaning how to do something:

• 使い方 = way of using / how to use
• 読み方 = way of reading / how to read
• 考え方 = way of thinking

In this sentence, 考え方 refers to a person’s mindset, ideas, or approach.

Both は and が are possible in many contexts, but they give slightly different nuances.

考え方は違います

This sounds like:

• As for ways of thinking, they differ
• It presents 考え方 as the topic
• It can also carry a slight contrastive feeling

考え方が違います

This would sound more like:

• The thing that differs is the way of thinking
• More direct focus on what is different

In this sentence, は works well because the speaker is making a general statement about people: even with the same textbook, their ways of thinking are different.

The subject is omitted because Japanese often leaves it unstated when it is understood from context.

English usually needs something like:

• Even if people use the same textbook...
• Even if students use the same textbook...

But Japanese often does not say that explicitly if it is obvious or meant generally.

So here, the sentence is making a broad statement about people in general. The implied meaning is something like:

• Even if people use the same textbook, ways of thinking differ from person to person.

In Japanese, nouns usually do not change form for singular vs. plural the way English nouns do.

So:

• 人 can mean a person or people, depending on context

In 人によって, it does not mean just one specific person. It means:

• depending on the person
• from person to person

This is a very common Japanese way to express general variation among individuals.

Yes, here 違います means is different / are different, but grammatically 違う is a verb, not an adjective.

Dictionary form:

• 違う = to differ / to be different

Polite form:

• 違います

So:

• 考え方は違います
• Ways of thinking differ / are different

This is one reason the sentence does not need a separate word meaning are. The verb 違います already carries the idea.

Both are possible, and the best choice depends on how natural you want the English to sound.

even if

Focuses more on the condition:

• Even if people use the same textbook, ...

even though

Focuses more on the fact:

• Even though people use the same textbook, ...

In Japanese, Vて + も can cover both kinds of meaning. In this sentence, the nuance is basically:

• using the same textbook does not guarantee the same way of thinking

So either translation is reasonable.

The comma marks a pause between the first clause and the main clause:

• 同じ教科書を使っても、
• 人によって考え方は違います。

It helps separate:

1. the concessive part: Even if/though they use the same textbook
2. the main statement: ways of thinking differ from person to person

In Japanese writing, commas are often used more flexibly than in English, but here it makes the sentence easier to read.

Yes. A simpler paraphrase would be:

• 同じ教科書を使っても、人それぞれ考え方が違います。

Here 人それぞれ means something like each person is different or each person has their own way.

Another possible paraphrase:

• 同じ教科書を使っても、考え方は人によって違います。

This keeps the same meaning but changes the word order slightly. Japanese allows that kind of flexibility more than English does.