K for DS is MUS Primer, HWT K, Headsprout, science based on Building Foundations of Scientific Understanding, lots of reading and currently some distasteful glances at Art Adventures at Home (I'm not feeling the love for that one currently).
DD1 (3 years old) wants to have something to do whenever I'm working with DS, so we have ETC Get Ready for the Code and HWT Pre-K workbooks to keep her from moving in on DS' workbooks, along with some Kumon cutting and tracing workbooks to help with her fine motor skills (and keep her from cutting the cats' whiskers and drawing on the walls).