(Sun-Times file)

1. Asking about clean coal technology down in the coal mine (main level).

2. Searching for and finding the image of the “Three Blind Mice,” a miniature of Excalibur (King Arthur’s sword) and Cinderella’s tiny glass slippers in Colleen Moore’s Fairy Castle (lower level).

3. Splurging the extra $5 for the guided, on-board tour of the U-505 submarine, the only German sub on display in the United States.

Hours: 9:30-4 p.m. Monday-Saturday; 11 a.m.-4 p.m. Sunday. General admission: $13 adults, $12 seniors and $9 children ages 3-11. More information: (773) 684-1414 or www.msichicago.org.

What are your favorite three things about the Museum of Science and Industry?