Today through Friday, the Museum of Science and Industry is offering free general admission, which covers exhibits including Earth Revealed, Farm Tech, and Fast Forward . . .Inventing the Future (Smart Home and Harry Potter: the Exhibition aren't free). Friday is also the grand opening for the Smart Home Farmers' Market, which will take place in the east parking lot from 7:30 AM to 2 PM on the first and third Friday of every month through October. Events include a cooking demo by the Hearty Boys at 11:30 AM, plus food cooked in a solar oven and music.