Alexandra and Anna learn about construction techniques at the Arizona Science Center's "Many Hands Make a Home" exhibit, trying out what they learn on a house for their dog, Rupert. Home Prickly Home: Alex and Mark head to the Arizona-Sonora Desert Museum to see which creatures make the Saguaro cactus home. And DFTV learns how Chase Field-the only sports facility in world that has a retractable roof, air conditioning, and natural turf-keeps its grass green and growing.