kono tougeikyousitu ha kodomotati ni kagirazu, otona mo sankasuru.

に限らず means not limited to ..., not فقط ..., or more naturally in English, not just ....

So:

• 子供たちに限らず = not limited to children
• whole sentence: This pottery class is not just for children; adults participate too.

This pattern is fairly common:

• X に限らず Y も ...
  = not only X; Y also ... = not limited to X; Y too ...

It is a somewhat formal or written-sounding expression compared with something like だけでなく.

In this grammar pattern, 限らず normally takes に before the thing that is being treated as the limit.

So you learn it as a set expression:

• X に限らず = not limited to X

Here:

• 子供たちに限らず = not limited to children

This に is not the same as the に used for time, location, or indirect object. It belongs to the expression に限らず.

The は marks この陶芸教室 as the topic of the sentence:

• この陶芸教室は = As for this pottery class, ...

Japanese often sets up a topic first, then comments on it.

So the structure is roughly:

• As for this pottery class, it is not limited to children; adults participate too.

Even though 教室 is not the grammatical subject of 参加する, it can still be the topic. This is very common in Japanese.

も means also / too.

So:

• 大人も参加する = adults also participate

It matches the idea introduced by 子供たちに限らず. The sentence says the class is not only for children, and then adds that adults too take part.

Without も, the sentence would lose that too / also nuance.

たち is one way to indicate a plural group, especially with people:

• 子供たち = children

But Japanese does not always need an explicit plural marker where English does. A bare noun like 大人 can already mean:

• an adult
• adults

depending on context.

Here, 大人 clearly means adults because of the sentence meaning.

You could say 大人たち in some contexts, but 大人 is very natural here. Japanese often uses plural marking only when it is helpful or emphasized.

Because the thing being participated in is already understood from the topic:

• この陶芸教室は = As for this pottery class...
• 大人も参加する = adults also participate

In English, we would often say participate in this class, but Japanese often omits information that is obvious from context.

A more explicit version would be something like:

• 大人もこの陶芸教室に参加する

But that sounds less natural here because この陶芸教室 has already been introduced as the topic.

Yes. When you state what someone participates in, 参加する often takes に:

• 授業に参加する = participate in class
• 会議に参加する = participate in a meeting

So if you spelled everything out here, it would be:

• 大人もこの陶芸教室に参加する

But Japanese often leaves that part out when it is already clear.

陶芸教室 is a compound noun:

• 陶芸 = pottery / ceramic art
• 教室 = class / classroom / lesson group

Together:

• 陶芸教室 = pottery class

There is no need for の here. Japanese often combines nouns directly to form one compound noun.

So:

• この陶芸教室 = this pottery class

And この modifies the whole compound noun 陶芸教室.

Yes, generally に限らず sounds a bit more formal, objective, or written.

Compare:

• 子供たちに限らず、大人も参加する。
  = more formal / explanatory
• 子供たちだけじゃなくて、大人も参加する。
  = more conversational

Both are understandable and natural, but に限らず is especially common in writing, announcements, and formal speech.

Yes. A very similar version is:

• この陶芸教室は、子供たちだけでなく、大人も参加する。

That also means:

• This pottery class is not only for children; adults participate too.

The difference is mainly nuance:

• に限らず = not limited to
• だけでなく = not only

In this sentence, both work well.

The comma helps separate the first idea from the second:

• 子供たちに限らず、 = not limited to children,
• 大人も参加する = adults also participate

Japanese commas are often used more flexibly than English commas. Here it makes the sentence easier to read by clearly dividing the not limited to X part from the Y also ... part.

It is especially natural after expressions like に限らず, where the sentence is transitioning to the added category.

Yes, that is the literal structure, but the natural meaning is that participation in the class is not limited to children.

Japanese often phrases things this way:

• この教室は子供に限らない
• literally: This class is not limited to children
• natural meaning: This class is not just for children

So the sentence is describing the class in terms of who can or does participate in it.

It is the plain non-past form, which in Japanese can cover both present and future depending on context.

Here it expresses a general fact or habitual situation:

• 大人も参加する = adults also participate

It does not necessarily mean one specific future event. It sounds more like a general description of the class and who joins it.