President Obama emphasized at a summit of leaders from across the Americas that the U.S. would not shift strategies in the war on drugs. His administration had, in recent weeks, faced criticism from some presidents who said the U.S. approach to the drugs trade had simply generated more violence in Latin America.

That wasn't the only thorny issue Obama faced in his trip to Colombia.

Norwegians will be confronted again this week with the terrible details and trauma of the worst peacetime attack in the country's history.

Police say last July 22, Anders Behring Breivik set off a car bomb in the center of Oslo near government offices. The blast killed eight people and spun residents and police into a state of chaotic alarm and confusion.

The midsection of the U.S. was wracked by storms and tornadoes overnight, with the National Weather Service's Storm Prediction Center forecasting more severe weather to come. Five deaths have been confirmed in northwest Oklahoma, the state's Department of Emergency Management tells NPR.

GOP presidential candidate Mitt Romney will spend the next seven months convincing us to send him to the White House. To get there, he'll have to make a strong case to one very important voting bloc: women.

A poll out this week by ABC and the Washington Post shows President Obama with a 19-point lead over Romney with women voters. For Romney to win, he's got to make a significant dent in that margin.

How do you measure who is an effective teacher?

More states are wrestling with that question, now that the Obama administration is encouraging schools to evaluate teachers with a combination of student test scores and classroom observations.

The question of whether teacher evaluations are reliable indicators for teacher effectiveness has long been controversial. But New York City reignited the debate when it rated thousands of teachers with test scores alone — and then released those ratings to the public.

Transcript

GUY RAZ, HOST:

It's WEEKENDS on ALL THINGS CONSIDERED from NPR News. I'm Guy Raz.

PRESIDENT BARACK OBAMA: It's simple. If you make more than $1 million every year, you should pay at least the same percentage of your income in taxes as middle-class families do.

(SOUNDBITE OF MUSIC)

RAZ: President Obama from his weekly Saturday video address talking taxes and his proposal for a millionaire's tax, the so-called Buffett Rule. James Fallows of The Atlantic is with me now for more on this story and others we're following. Hello, Jim.

Transcript

(SOUNDBITE OF CLOCK TICKING)

GUY RAZ, HOST:

NPR's Joel Rose has a round-up of the week's news in the Trayvon Martin shooting case. Neighborhood watch volunteer George Zimmerman is in jail and the legal case is moving forward.

Major storms have reached a swath of the Great Plains from Oklahoma City up through central Kansas and into Nebraska. Weekends on All Things Considered host Guy Raz speaks with Chance Hayes, the Warning Coordination Meteorologist at the National Weather Service office in Wichita, Kansas.