Here's your look at five stories we're following today:

1. Luxury condo: The groundbreaking is slated for today for a new "ultra luxury" condo tower at 5th and Walnut streets.

2. Ferguson shooting: Two police officers were shot overnight in Ferguson at a demonstration in the wake of the resignation of the city's embattled police chief.

3. Mayoral candidates and registration records: We're tracking a number of potential developments in the mayoral field. Bill Green, recently ousted as chairman of the School Reform Commission, has changed his voter registration from Democrat to "no affiliation" and says he's keeping his options open regarding a mayoral bid as an independent. Three-time Republican candidate Sam Katz has also switched his registration to independent and says he's waiting to make a decision about the race, but is launching a website today to discuss ways to improve the city. And Milton Street is set to formally announce his bid today as a Democrat, but records list him as an independent. Check out full coverage of the race from Philly.com, the Inquirer, the Daily News and other partners at The Next Mayor.

4. N.J. state tests: New Jersey Education Commissioner David Hespe is scheduled to appear before a state Senate committee this morning, where he is likely to face questions about the state's new, controversial standardized tests.

5. 100-year-old's art show: The first solo art exhibition for Frieda Lefeber -- who turns 100 this month -- opens today at Rosemont College's Lawrence Gallery.