Learn Hardcore German: In einer gerechten Gruppe hören die Großen auch auf die Wünsche der Kleinen. - In a fair group the big ones also listen to the wishes of the little ones.

Gruppe is feminine in German: die Gruppe.
The preposition in can take dative (location) or accusative (direction). Here it means in a fair group (as a situation/state) → location, so dative.
Feminine dative singular of eine is einer.
With einer in the dative, the adjective takes -en: einer gerechten Gruppe.

So “In einer gerechten Gruppe” = In a fair/just group (dative feminine singular).

Why is the verb “hören” before the subject “die Großen”? I thought German word order was Subject–Verb–Object.

German main clauses follow the verb‑second (V2) rule: the finite verb is always in second position, but the first position can be many things (subject, time phrase, place phrase, etc.).

Here, the first element is the prepositional phrase: In einer gerechten Gruppe
Therefore the verb must come second: hören
The subject die Großen comes after the verb.

Structure:

In einer gerechten Gruppe (1st slot)
hören (2nd slot = finite verb)
die Großen (subject)
auch auf die Wünsche der Kleinen.

If you start with the subject, you’d say: Die Großen hören in einer gerechten Gruppe auch auf die Wünsche der Kleinen. The meaning is the same; only the emphasis changes slightly.

Why are “Großen” and “Kleinen” capitalized, and what exactly do they mean here?

They are adjectives used as nouns, called nominalized adjectives. In German, when an adjective stands alone with an article and functions as a noun, it is capitalized.

die Großen ≈ the big ones, here usually the older/stronger/more powerful people (often adults or bigger kids).
der Kleinen ≈ of the little ones, usually the younger/smaller/weaker people (often children).

This is similar to English expressions like “the rich,” “the poor,” “the young,” which also use adjectives as nouns.

Does “die Großen” mean “tall people,” “big people,” or “adults”? How should I understand it?

Literally die Großen = the big ones. The exact meaning depends on context:

With children: die Großen usually means the older kids (or adults) vs. the younger kids.
More generally: it can mean those who have more power, status, or authority.

In this sentence, in contrast to die Kleinen, it’s best understood as “the older/stronger or more powerful ones (e.g. adults or bigger kids)” rather than literally “tall people.”

What is the difference between “hören” and “auf … hören” in this sentence?

hören alone = to hear (perceive sound) or sometimes to listen:
- Ich höre Musik. – I’m listening to music / I hear music.
auf jemanden/etwas hören = to listen to / to heed / to follow (someone’s wishes, advice, orders):
- auf die Wünsche hören – to listen to / pay attention to the wishes
- auf die Eltern hören – to obey / listen to your parents

In “hören die Großen auch auf die Wünsche der Kleinen”, it means:
“the big ones also listen to / take into account the wishes of the little ones.”

Is “hören … auf die Wünsche” the same as the separable verb “aufhören” (to stop)?

No, these are two different things that happen to look similar:

hören … auf + Akkusativ (verb + preposition):
- auf is a preposition meaning on / to.
- auf die Wünsche is its object in the accusative.
- Meaning: to listen to / heed:
  - auf die Wünsche hören – to listen to the wishes.
aufhören (one separable verb) = to stop, to cease:
- Hör(t) auf! – Stop!
- Sie hört zu sprechen auf. – She stops talking.

In the sentence given, it is clearly hören + auf (preposition), not aufhören.

What case is “die Wünsche der Kleinen”, and how is it constructed?

die Wünsche = plural of der Wunsch (wish).
- Here it is accusative plural as the direct object of hören (auf).
- Nominative and accusative plural of most nouns with die look the same: die Wünsche.
der Kleinen = genitive plural of die Kleinen.
- Article: all-genitive-plural article is der, regardless of gender.
- Adjective ending -en: Kleinen.

So structurally:

auf die Wünsche – to the wishes (accusative object of the preposition auf),
der Kleinen – of the little ones (genitive attribute: whose wishes?).

Full phrase: die Wünsche der Kleinen = the wishes of the little ones.

Could you also say “die Wünsche von den Kleinen” instead of “der Kleinen”? Is there a difference?

Yes, you could say:

auf die Wünsche von den Kleinen hören

Both “der Kleinen” (genitive) and “von den Kleinen” (von + dative) are grammatically correct and understandable.

Nuance:

Genitive (der Kleinen) is a bit more compact and slightly more formal/standard in written German.
von + Dativ (von den Kleinen) sounds a bit more colloquial and spoken‑like.

In many everyday contexts, especially speech, von den Kleinen is very common. In written, somewhat more formal German, der Kleinen is very natural and often preferred.

What does “auch” do in “die Großen auch auf die Wünsche der Kleinen”, and could it be placed somewhere else?

auch = also / too / as well. Here it indicates that the big ones do this as well, not only someone else.

Position in the original:

hören die Großen auch auf die Wünsche der Kleinen.
→ auch comes after the subject and before the prepositional object.

You can move auch to change the emphasis slightly:

Auch die Großen hören auf die Wünsche der Kleinen.
→ Emphasis: The big ones also (not just the little ones / others) listen…
Die Großen hören auch auf die Wünsche der Kleinen.
→ Very similar to the original; auch is connected with the verb phrase “listen to the wishes of the little ones (too).”

All of these are correct; the basic meaning “also / too” stays, but the focus (who or what is “also”) shifts a bit.

Can the overall word order of the sentence be changed while keeping the same meaning?

Yes, as long as you respect the verb‑second rule, you can rearrange some parts without changing the core meaning. Examples:

Die Großen hören in einer gerechten Gruppe auch auf die Wünsche der Kleinen.
- Subject first; more neutral order.
Auch in einer gerechten Gruppe hören die Großen auf die Wünsche der Kleinen.
- Emphasis that even in a fair group this happens.
Auch die Großen hören in einer gerechten Gruppe auf die Wünsche der Kleinen.
- Emphasis that the big ones too listen.

In all these versions, the grammar is correct and the basic message remains:
In a fair group, the big/older ones also listen to the wishes of the little ones.