Top current and former executives from the country's two largest credit ratings agencies, Moody's and Standard & Poor's, testify today before the Senate Permanent Subcommittee on Investigations. Internal emails released yesterday by a federal commission investigating the financial crisis show that credit rating agency employees may have deliberately rated some mortgage-backed securities for Goldman Sachs higher than they should have. Jesse Eisinger, senior reporter for ProPublica is our guest.

Hundreds of thousands of teachers are facing layoffs this June as states and localities take drastic money-saving measures. We get an overview from Tamar Lewin, national correspondent for the New York Times. We also speak with Princeton sociologist Thomas Espenshade, who has crunched the numbers on what it takes to get into select colleges. He says we spend a lot of time arguing about things like affirmative action, but what we really need is a new Manhattan Project to tackle the persistent racial gaps in academic performance. Espenshade is co-author of  "No Longer Separate, Not Yet Equal: Race and Class in Elite College Admission and Campus Life."

Arizona Governor Jan Brewer faces a Saturday deadline to act on the nation's toughest legislation against illegal immigration. The sweeping measure would make it a crime under state law to be in the country illegally. It would also require local police officers to question people about their immigration status if there is reason to suspect they are illegal. Mark Brodie, who covers politics for KJZZ joins us from Phoenix with the latest.

We hear from you about some of our recent stories, including a discussion about carrying guns in public and a conversation with author Steve Almond about his love for rock and roll music.

On the 20th anniversary of Hubble telescope, Nate DiMeo of the Memory Palace podcast, brings us the story of the "unbelievable" discoveries of a British Astronomer in the 1800's that were reported in the New York Sun newspaper. "Unbelievable" because they turned out to be a hoax.

The prolonged absence of musical director James Levine from the podium at the Boston Symphony Orchestra due to health problems started us to thinking about the void his absence leaves in the musical world. We ask music critic Lloyd Schwartz who are some of the hot musical directors to watch. (See music titles from this story below.)

• Peter Dixon, "Nagog Woods"
• Art Blakey, "C.O.R.E."
• Funk Brothers, "Keep Me Hangin' On"
• Ahmad Jamal, "Patterns"
• Stevie Wonder, "Easy Goin’ Evening (My Mama’s Call)," from Songs in the Key of Life
• Dan Deacon, "Snookered"
• Christian McBride, "Brother Mister"

From "Bright Young Stars" story:

• Maurice Ravel, "Daphnis and Chloe," performed by James Levine and the Boston Symphony Orchestra
• Ludwig van Beethoven, "Symphony Number 5 in C Minor," Op. 67 III. Allegro, performed by Gustavo Dudamel & Simon Bolivar Youth Orchestra of Venezuela
• Gustav Mahler, "Symphony Number 8 in E-Flat Major: Part I-III Infunde Amorem Cordibus," performed by Michael Tilson Thomas and The San Francisco Symphony
• Johannes Brahms, "Symphony Number 2: Hungarian Dances: No. 1 in G. Minor," performed by Marin Alsop and the London Philharmonic Orchestra
• George Bizet, "Carmen Entr’acte to Act 4," performed by Yannick Nezet Seguin and the Metropolitan Opera Company Orchestra