"All children" shoud't be Kol Yeladim? Kol HAyeladim shoud't be all THE children (from a specific group)?
In Hebrew you can't say כל ילדים. Plural is always definite, so it can be only כל הילדים.
What is wrong with the translation, All the children like to win? It is a perfectly good English sentence and an exact translation of the Hebrew. But Duo didn't like it.
If it didn't accept it, it means it's not in the database. Did you report it?
Since this lesson is "infinitives" shouldn't the translation be "to win"?
Infinitives in Hebrew. English permits both infinitive and gerund after the verb "like".