Date night

Every Tuesday night my wife and I go out and have datenight. The first thing we do is go out to eat. We have a list of all the restaurants in Waco, and we chose one and go. But the problem is coming up with fun ideas for after dinner. We have a limited amount of time, since we have a 12 year old son. We leave the house at 6:30, and have to be back by no later than 9:59. Mostly all we do is either go see a movie, or go wander around at the bookstore, or go get ice cream. A couple times we have gone bowling. But I'm having a hard time coming up with new good ideas for our date night. Sometimes (like right now) money is short and we need ideas of cheap things to do, and other times we have a little extra spendin' money. Anyone out there have any great ideas of fun things to do around Waco on a Tuesday night????? Help a brotha out!!