By Terri Rimmer If you’re looking for some fun and free family activities in Dallas and/or Fort Worth, TX, try these on for size: Cedar Hill State Park at 1570 FM 1382, ten miles south of Dallas has the best bike trails. On the weekends you can’t stir the bicycles with a stick. For information, call 972-291-3900. The best free entertainment for a kid can be found at Founder’s Plaza at DFW International Airport at 2829 30th Street (Carbon Road) in Dallas. Little kids who like airplanes, trucks, and other big stuff will truly be thrilled to spend an hour watching the jets come and go from this busy airport. The best place to see pets run wild is at the Off-Leash Dog Park at Mockingbird Point near the intersection of Mockingbird and West Lawther. The city set aside some park land at the northeast corner of the lake. For information, call 214-670-4100. The best playground is at Andrew Brown Community Park East at 260 E. Parkway Boulevard in Coppell. The town doesn’t exactly come to min...