Chicago is nothing if not all about all that jazz, and August 28 through August 31 is the Windy City’s way of giving all its local hepcats something to celebrate. The 30th Annual Chicago Jazz Festival will take place in both Millennium Park and Grant Park (though today’s performances will only be in the latter venue) and will feature talent ranging from the Chicago Bass Masters to the Sean Jones Quintet. Don’t fret if your brood seems more into Laurie Berkner than Josh Berman and His Gang – this year, there’s a new Children’s Tent in Grant Park where kids can learn about all the different instruments and music that comprise the sublime sounds of jazz. Best of all, however, this event is free, so you won’t be wasting a wad of bills to show up and then leave early when your little Miles Davis-in-the-making has a meltdown.