Floyd Mayweather Jr and Shane Mosley with a showdown boxing match on HBO pay-per-view.

The 136th running of the Kentucky Derby, the first jewel in horse racing’s Triple Crown

Michigan becomes the 38th state to ban smoking in most public places.

Speaking of Michigan, President Obama will be delivering the commencement address at the University of Michigan.

2010 White House Correspondents Dinner, with Jay Leno as the entertainment.

Join Hands Day (www.joinhandsday.org)

National Home Brew Day. Last year, more than 5,000 people celebrated by brewing over 13,000 gallons at 342 sites on six continents worldwide.

NBC’s MEET THE PRESS features a new set beginning today, plus its debut in HD.

Conan O’Brien with his first post-Tonight Show interview, on 60 MINUTES.

Start of Be Kind to Animals Week, as well as National Anxiety and Depression Awareness Week

CBS-TV with the season finale for COLD CASE

Melanoma Monday (www.aad.org)

The American Federation for Children national policy summit, in Washington, D.C. The event intends to inform and encourage school choice supporters to promote school choice programs in their own states and communities and will feature some of the nation’s leading public policy-makers and analysts.

National Teacher Day (www.nea.org)

A full day of commemorative events are planned at Kent State today, the 40th anniversary of the May 1970 national guard shootings.

Sentencing day for Robert Halderman, who pleaded guilty to attempted grand larceny for plotting to extort money from David Letterman.

Nominations for the 64th Annual Tony Awards will be announced today.

Motor vehicle sales figures for the month of April are announced.

Cinco de Mayo

Vice President Joe Biden heads to Brussels, Belgium, and Madrid, for a trip that will include him delivering a “major” address to the European Parliament.

Jose Canseco testifies in front of a Washington DC grand jury, as prosecutors look to build a case that Roger Clemens lied in Congressional testimony concerning his use of performance-enhancing drugs.

National Day of Prayer

Parliamentary elections in England, with the reign of British Prime Minister Gordon Brown in the balance.

Federal Reserve Chairman Ben Bernanke speaks to the Chicago Federal Reserve Bank 46th Annual Conference on Bank Structure.

First Friday of the month, and that means April’s unemployment number will be released at 8:30AM ET.

NBC-TV with the season premiere of FRIDAY NIGHT LIGHTS (following its original run on DirectTV)

Ultimate fighter Kimbo Slice’s career continues with a bout against former NFL player Matt Mitrione at UFC 113 in Montreal.

In Missoula, MT, opening of the International Wildlife Film Festival

Cornelia de Lange Syndrome Awareness Day

Mother’s Day

The FDA approved use of the birth control pill, 50 years ago today.

CBS-TV with the season finale for THE AMAZING RACE 16

World Lupus Day (www.lupus.org)

Start of National Stuttering Awareness Week

In Colorado Springs, first annual Warrior Games, featuring competition among about 200 amputees and other injured soldiers.

National Women’s Check-Up Day

NBC-TV with the season finale for TRAUMA

In Los Angeles, cable execs gather for the annual “Cable Show” convention.

National School Nurse Day (www.nasn.org)

National Receptionists Day

Opening of the 63rd Cannes Film Festival

Microsoft officially launches software package “Office 2010” to businesses today.

Nominations for the 37th Annual Daytime Emmy Awards are announced

NBC-TV with the season finale for MERCY.

THE CW with the season finale for AMERICA’S NEXT TOP MODEL.

ABC-TV with the season finale for PRIVATE PRACTICE

THE CW with season finales for THE VAMPIRE DIARIES, and SUPERNATURAL.

In Charlotte, NC, the National Rifle Association’s Annual Meeting. Sarah Palin is among the featured speakers.

Retail sales figures for April, a sign whether consumers are spending again, are released.

THE CW with the season finale for SMALLVILLE.

The 2nd jewel of horse racing’s Triple Crown, the Preakness Stakes

In Magnolia, AR, the World Championship Steak Cook-Off (www.blossomfestival.org)

First Lady Michelle Obama speaks at the George Washington University commencement.

ABC-TV with the season finales for DESPERATE HOUSEWIVES and BROTHERS & SISTERS.

CBS-TV with the season finale for SURVIVOR: HEROES VS VILLAINS

NBC-TV with THE 2010 MISS USA PAGEANT, live from the Planet Hollywood Resort & Casino in Las Vegas.

Start of National Dog Bite Prevention Week

THE CW with the season finales for ONE TREE HILL and GOSSIP GIRL

HIV Vaccine Awareness Day

Housing starts figures for April are released.

Mount St. Helens erupted 30 years ago today, killing 57 people.

THE CW with the season finale for 90210.

National Employee Health & Fitness Day

The minutes from the Fed’s last meeting are released.

Mexican President Felipe Calderon and his wife visit the White House for a state dinner. And you know what story that event will dredge up.

NBC-TV with the season finale for LAW & ORDER: SVU

Germany hosts an international conference to discuss regulatory and supervisory reform of financial markets

Former Detroit mayor Kwame Kilpatrick is sentenced after being judged to have violated terms of his probation after pleading guilty to obstruction of justice charges. The bench has advised him to “have his affairs in order,” so it appears immediate jail time is imminent.

ABC-TV with the season finale for GREY’S ANATOMY

CBS-TV with the season finale for CSI and THE MENTALIST

National Bike to Work Day

CBS-TV with the season finale for GHOST WHISPERER

Start of National Safe Boating Week

ABC-TV with the series finale for LOST.

NBC-TV with the season finale for CELBRITY APPRENTICE.

Existing home sales for April are released

Israeli troops ended 18 years of occupation pulling out of south Lebanon, ten years ago today.

ABC-TV with the performance finale for DANCING WITH THE STARS

CBS-TV with the season finale for CSI: MIAMI

FOX-TV with the series finale of “24”

NBC-TV with the season finale for LAW & ORDER

ABC-TV with the results finale for DANCING WITH THE STARS

CBS-TV with the season finale for NCIS, NCIS: LOS ANGELES, and THE GOOD WIFE

NBC-TV with the season finale for THE BIGGEST LOSER, and PARENTHOOD

Durable goods sales figures for April, big ticket items that point to a more confident consumer, are released

CBS-TV with the season finale for CRIMINAL MINDS and CSI:NY.

Gross Domestic Product for April, the metric of whether the economy is growing and at what pace, released at 8:30am ET.

Supreme Court Justice David Souter delivers the commencement address at Harvard.

ABC-TV with the season finale for FLASH FORWARD

NBC-TV with the premiere of the new comedy series 100 QUESTIONS, about a woman who hits an online dating service to find Mr Right

Jay Leno band leader Kevin Eubanks says tonight will be his last TONIGHT SHOW

The 93rd running of the Indianapolis 500.

American teenager Natalee Holloway was last seen in Aruba, five years ago today. Her fate remains unknown.

Memorial Day

World No Tobacco Day