What can i do for my kids?

I was wondering what kind of things I can do to keep my kids sort of busy though out the day so they don't be watching tv all day now that school is out there ages are 5,4,2,1the two older ones just finished k, and prek so I was wondering what the two older ones can do to keep busy but also be ready for this school year comin they'll b in 1st,and k also some stuff that could involve the younger ones as well anything will help thanks