You don't need to use "some" in English or Spanish. In the English original, "some" is a bonus word. The sentence is semantically identical when it is omitted:
I made hot chocolate for the kids.
is the same as
I made some hot chocolate for the kids.
No one would think that you made none or all of the hot chocolate if you omit the "some".
In Spanish, you can omit "some":
Preparé chocolate para los niños.
is the equivalent of
I made some hot chocolate for the kids.
You don't really need caliente since the candy form of chocolate would be a dulce of one kind or another.
Caution: when you use algo in Spanish, it can have another meaning that does not appear to be intended here.
In the sentence Había algo de nieve en la calle., the term algo suggests a final remnant of small quantity, a scant presence or hint. That's definitely not what I understood you meant by "I made some hot chocolate for the kids."
Preparé algo de comida y fui a dormir would translate as "I made myself something to eat and went to sleep." The algo suggests that whatever you made, it wasn't substantial and that you were in a hurry to get to sleep.