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.