crawdude

my two cents…having an entire week available to you allows for a trip much further from home than what one could do with say a long weekend, not knowing your family demographics or interests but having been to DV I would say go further, DV is nice but IMO not enough there to fill a weeks activities, especially since it may still be a little cool out for swimming

my tribe has a schedule of which parks we visit during the year, we usually head west earlier than the crowds and hit the Big Bend area in late February, schools are out for presidents day and amazingly our kids were always running a fever the Friday before (schools have gotten a little unreasonable about excused absences and sometimes a little white lie can mean the difference between a mediocre day of learning and four days of amazingly educational life experiences out in the geology and nature of our state), anyway we always made this our Big Bend weekend, but we only had to travel from Austin, warm days followed by hot soaks in the spring in the cool evening air, and no crowds

but back to your trip…I suggest you head far and head south, there are some awesome parks close to you, Mineral Wells, Daingerfield, Caprock Canyons, Abilene, Brownwood, but save these for later in the year when the heat, humidity and mosquitoes return to the coastal areas, March is the time to enjoy the coastal area of our state before all of the aforementioned return, and seeing a dinosaur track is cool, but seeing a live dinosaur (alligator) is way cooler, and Brazos Bend is a place to do that

another good one for kids is Goliad, kids like forts, and they like to climb on things, and Goliad has lots of that, the Mission, Presidio la Bahia a paddling trail, museums, even a petting zoo last time I was there, we have always seen lots of critters on our hikes there and there are great antique shops in Goliad and Gonzales

as someone else suggested there is Inks, which is very bueno, and it offers the option of day trips to longhorn cavern (how cool are caves? real cool) and if you know how to play the number game you can enjoy a drive to Enchanted Rock which is within range of a day trip during your week (kids like rocks and enchanted rock is one seriously big rock)
avoid the temptation to see Colorado Bend, it is a fish camp on a river way, way, way down a dirt road, beautiful spot on a river to paddle but a long way out of the way to go to visit another dot on a map

anyhoo, that’s my two cents