Nurith Aizenman

Our blog often features stories about efforts to improve life for this planet's 7 billion inhabitants: how to make sure everyone has access to clean water and power, medical care to stay healthy, enough income to feed their kids, education for the children so they can fulfill their potential.

Pakistan's latest polio eradication drive got off to a tragic start last week when gunmen killed a mother-daughter vaccination team in the Western city of Quetta. Sakina, 38, and her 16-year-old daughter, Rizwana, were administering immunization drops to children when the assailants sped past on a motorbike and shot each woman in the head. (Like many people in Pakistan, Sakina and Rizwana only went by a first name.)

Many immigrants from El Salvador are in a state of shock. On Monday, the Trump Administration announced that it will soon be ending a humanitarian program that has allowed nearly 200,000 of them to live and work in the U.S. since 2001, after two earthquakes devastated their country. Now they worry for their future.

But the potential pain is likely to prove just as acute in El Salvador. That's because nearly all these Salvadoran immigrants work — and a huge share of them regularly send a portion of their earnings to family in El Salvador.

What are the hidden messages in the storybooks we read to our kids?

That's a question that may occur to parents as their children dive into the new books that arrived over the holidays.

And it's a question that inspired a team of researchers to set up a study. Specifically, they wondered how the lessons varied from storybooks of one country to another.

For a taste of their findings, take a typical book in China: The Cat That Eats Letters.

The loan was tiny. Just $19 to buy a bus ticket. But for Mariful Islam, the difference it made was immense.

Islam is 24. He has lived in the same rural village in Bangladesh his whole life. He doesn't own his own land. So he scrapes out a living working on other people's farms.

"Mostly I plant and I harvest rice in the paddies," he says.

Critics are heaping praise on a new off-Broadway play about life in modern Africa. But if you're assuming the topic must be war or disease or famine, you're in for surprise.

This play is about ... mean girls.

School Girls; or, The African Mean Girls Play — running at New York City's MCC Theater through December 31 — is set in at a boarding school in Ghana in the 1980s, where the ruthless queen bee seems unstoppable until an exotic new girl arrives from Ohio.

There's new — and shocking — evidence about the toll that health care costs are taking on the world's most vulnerable.

Editor's Note:This story was originally published in November 2016 and has been republished with updates.

It's the sixth annual #Giving Tuesday — a holiday marketing tradition inspired by Black Friday, Small Business Saturday and Cyber Monday, but with a twist. Today thousands of charities are asking us to open our wallets. But how can we be sure the group we donate to is effective — that we're getting the most bang for our charity buck?

The latest statistics on child labor are in — and they're not encouraging.

An estimated 152 million children around the globe are doing work that prevents them from getting an education or that's harmful to their health. That's almost 1 in 10 children worldwide.

The figures, which cover 2016, were released this week in a report by the United Nations' International Labour Organization.

Here are eight more takeaways:

Editor's Note: This story was originally published in August and has been updated.

The national news this week has been dominated by accusations against U.S. Senate candidate Roy Moore — both the allegations that he sexually assaulted at least two teenage girls and also that he attempted to date teenagers while he was in his 30s.

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