One of the things that’s so different about digital journalism is the metrics. In the old days of print-only journalism, we knew how many papers we printed each day, but we didn’t know how many people actually read those newspapers.

Now, in the world of all things digital, we have far more information than we could have ever imagined. In a routine that can be either encouraging or discouraging, we have the ability to look deeply into the metrics for each and every story — how many visits on our web page, where did they come from, did the readers come to us from a recommendation on Facebook or notice the story while reading something else, how long did they spend reading, did they share the story with their Facebook friends — you name it, practically everything you could want to know about the readers of a particular piece of journalism.

So when we noticed this week that two of our investigative stories were getting unusual traffic, it raised questions for us. And of course, we dug into the metrics.

Alan Judd’s story about segregation of students with disabilities in public schools was published July 16. The story detailed the U.S. Justice Department’s charge that Georgia is illegally segregating students with disabilities in separate schools that are old, dirty and poorly maintained. One school in the Georgia Network for Educational and Therapeutic Support requires disabled students to use segregated restrooms and an entrance that keeps them apart from other children. Another school reportedly makes disabled students stay in the basement all day. Others lack libraries, gymnasiums, science labs, cafeterias, playgrounds: just about every other amenity that is taken for granted in regular schools.

By forcing students to attend such programs, the Justice Department says, Georgia is violating the Americans with Disabilities Act. The department is threatening to take the state to court to force compliance.

Judd’s story about this got respectable traffic the day it was published and the next day, but then the numbers faded, as they typically do after news stories run their course. But last week, the numbers started climbing again and Judd dug in to figure out what was behind the resurgence.

Traffic from Brazil? Readers in Argentina? What was the international interest in this story about the way Georgia treats disabled students?

It turns out the story was tweeted — that’s digital-speak for shared — by the Twitter page for MattyB, a wildly popular young entertainer from Gwinnett County. I’ll tell you more about MattyB in a minute, but first a little about his family’s interest in the story.

MattyB, Matthew Morris, has a 9-year old sister who was born with Down syndrome. (She’s an entertainer too; check her out at

or

)

According to Matt’s father, Blake Morris, Sarah Grace attends Level Creek Elementary, a Gwinnett County public school. She takes some special classes to help with her special learning needs, but for at least half of each day, she spends time with the general student population.

Morris says since Sarah Grace started school, her family has worked with the school system to keep her in the general population of students as much as possible. Research shows mildly disabled students thrive when schooled with non-disabled students, and federal law requires that disabled public school students be placed in the least restrictive environment possible.

The Morris family is in the midst of a three-year legal battle to keep Sarah Grace in an environment they feel is best for her, while Gwinnett Public Schools has argued for more specialized instruction in segregated special education classes.

During that court battle, which is in the appeals stage, Sarah Grace has been attending Level Creek. Morris said the family believed they had an agreement with the school system that she could stay there until the court matter was resolved. The family feels she has been thriving there.

However, they got a notice that the school system was reassigning Sarah Grace to a different environment at Sycamore Elementary beginning immediately. Morris said the family is not sure exactly what that will mean for Sarah Grace, but they are heartbroken. She does not want to leave her friends or community at Level Creek and they fear she will not do as well in a new environment.

Which brings us to the tweet from her brother’s account. His father manages that account and decided to use it to call attention to Judd’s story about segregation of disabled students and Sarah Grace’s reassignment.

“We haven’t used Matt’s platform,” to bring attention to this before, Morris said. But Sarah Grace is a big part of Matt’s life and many of his fans are aware of her situation and follow her as well. “Matt doesn’t understand why Sarah’s being shipped off,” Morris said. “If I can expose this, I want to.”

Expose he did. MattyB has 685,000 Twitter followers and many around the world visited the story or re-tweeted the item. I think it’s safe to say that it’s the first time one of our investigative stories has been tweeted by Perez Hilton, a huge celebrity and a friend of Matt’s. And we’re still not sure if the re-tweet by Justin Bieber is authentic.

Of course, Matt is a huge celebrity himself; his web page is MattyBRaps.com. Since he was 7, he’s been recording music videos on YouTube. He was influenced by a musically inclined cousin who competed on American Idol. If you have not heard of MattyB, you probably are not in the right age bracket. But oodles of people have – he has 2 billion views on YouTube and 7.6 million Facebook fans.

Morris said MattyB’s lyrics and production are all family friendly — no profanity, drugs or suggestive language. His cousin writes lyrics and produces the videos and they are often youth-oriented covers of popular songs. One song, a cover and rap to Cyndi Lauper’s “True Colors” is about bullying and the ability of people like Sarah Grace to bring people together. MattyB is a charming blond, 12-year-old suburban rapper who has drawn 4.4 million subscribers on YouTube.

The celebrity is unexpected and growing, so Morris said it is important for the family to “keep it contained.” Matt’s still a middle school student and they don’t want this all to get too big for him. Every so often, they ask him if it’s still something he enjoys. And so far, he does.

Which is good news for his followers in Argentina, where the Facebook fan page has 2,800 likes. Some of whom this week apparently read our investigative story on ajc.com.

Our other investigative story that got unexpected traffic this week got it in a more conventional way. Brad Schrade’s story on a tragic Glynn County police shooting was covered by a writer for Esquire. “It is a perfect case study of the problems with police culture in this country — most notably, the near impossibility of getting the justice system to deal with police who kill people. It is a true American horror story,” wrote Charles P. Pierce in an essay on Esquire.com. His essay drew the attention of other news organizations, including The Washington Post and Daily Kos.

The unexpected attention boosted visibility of the story, and it’s now been read by users in the Netherlands and New Zealand.

It’s all a pretty powerful testament to the relevance and reach of our investigative reporting. You, our hometown readers, are still our most important audience. But it’s nice to know we can draw traffic worldwide to important work.