Djeca žele skočiti u veliku lokvu.

Djeca means children, while dijete means child.

This is an irregular plural:

• dijete = child
• djeca = children

So because the sentence talks about more than one child, Croatian uses djeca.

Because djeca is plural in meaning, the verb agrees with it:

• dijete želi = the child wants
• djeca žele = the children want

So žele is the 3rd person plural form of željeti (to want).

Croatian often uses a finite verb + infinitive structure, just like English:

• They want to jump
• Djeca žele skočiti

Here:

• žele = they want
• skočiti = to jump

After verbs like željeti (to want), Croatian commonly uses the infinitive.

This is about aspect, which is very important in Croatian verbs.

• skočiti = perfective → to make one complete jump / to jump in
• skakati = imperfective → to be jumping / to jump repeatedly / habitually

In this sentence, the idea is that the children want to do a single completed action: jump into the puddle. That is why skočiti fits well.

Compare:

• Djeca žele skočiti u lokvu. = The children want to jump into the puddle.
• Djeca vole skakati po lokvama. = The children like jumping in puddles / like to jump around in puddles.

Because u can take different cases depending on meaning.

Here, u means into, showing movement toward the inside of something, so it takes the accusative.

• lokva = puddle
• lokvu = accusative singular

And the adjective must match:

• velika lokva = a big puddle
• u veliku lokvu = into a big puddle

So:

• u + accusative = motion into
• u + locative = location in

Compare:

• Skočiti u lokvu = to jump into the puddle
• Biti u lokvi = to be in the puddle

Because veliku is the accusative singular feminine form of velik (big), and it must agree with lokvu.

Agreement in Croatian means the adjective changes to match the noun's:

• gender
• number
• case

Since lokva is:

• feminine
• singular
• accusative

the adjective must also be:

• feminine
• singular
• accusative

So:

• velika lokva = a big puddle
• u veliku lokvu = into a big puddle

Lokva is the dictionary form, the nominative singular.

In the sentence, the puddle is the destination of movement after u, so Croatian uses the accusative singular:

• lokva → nominative
• lokvu → accusative

This kind of noun change is very normal in Croatian and happens because nouns change form according to their role in the sentence.

Croatian has no articles, so it does not use words like the or a/an.

That means:

• djeca can mean children or the children
• veliku lokvu can mean a big puddle or the big puddle

The exact meaning depends on context.

So Croatian expresses the idea without articles, even though English usually needs them.

Yes. Croatian word order is more flexible than English because case endings show grammatical roles.

The neutral order here is:

• Djeca žele skočiti u veliku lokvu.

But other orders are possible for emphasis, for example:

• U veliku lokvu djeca žele skočiti. = Into the big puddle is where the children want to jump.
• Skočiti u veliku lokvu djeca žele. = It is jumping into a big puddle that the children want.

Even though the order can change, the original version sounds natural and neutral.

A rough pronunciation guide is:

• Djeca ≈ DYE-tsa
• žele ≈ ZHEH-leh
• skočiti ≈ SKO-chee-tee
• u ≈ oo
• veliku ≈ VEH-lee-koo
• lokvu ≈ LOK-voo

A few helpful sounds:

• dj / dje in djeca is softer than English j; in many pronunciations it sounds close to dy
• ž sounds like the s in measure
• č sounds like ch in church

Yes. Djeca is treated as a plural noun in sentences like this, so it takes plural agreement:

• Djeca žele = The children want

It is not formed with a regular ending like many other nouns, so learners simply need to memorize it as the plural of dijete.

A useful pair to remember is:

• jedno dijete = one child
• dvoje djece / djeca = children

So even though the form is irregular, its behavior here is straightforward: it goes with a plural verb.

Yes, that is possible, but it is a bit different in tone.

• žele = want, wish, desire
• hoće = want / are willing / intend to

In many contexts both can work, but žele often sounds a bit more neutral or descriptive here. Hoće can sometimes sound stronger, more immediate, or more conversational depending on context.

So your original sentence is perfectly natural, and žele is a very good choice.