"Ya" - Yes, just "ya."

I was in Colombia recently, long story short, working with 6-7 year olds in school. I went up and down the aisles asking them the English word for various colors - simple stuff - and I got turned around and started asking kids that I had already asked, and all they said, one after the other, was "ya." I confirmed that that they were using "ya" in its usual meaning of "already," they just didn't add any details, as in "me preguntaste ya." Someone else told me that the single word "ya" can also mean "I understand" or "I got it" as in if a mom said to her kid "No olivides limpiar su cuarto" the kid might answer "Ya." Sound right? And are there any other uses?