In my 30 years writing about schools, one reader question outnumbers all others: “I like where I live, but I have kids now and the local school doesn’t look good to me. What should I do?”

I tell them how to investigate their neighborhood school. I explain that children of education-focused parents like them learn a lot no matter what school they attend. Then I advise them to go with their gut. Even if everybody thinks their local school is great, if it doesn’t feel right they should send their kids elsewhere.

I’ve done a long magazine piece and lots of columns on this, but I have never seen the issue dissected as well as in a new book by Washington area parent Michael J. Petrilli, “The Diverse Schools Dilemma: A Parent’s Guide to Socioeconomically Mixed Public Schools.” It is deep, up-to-date, blessedly short (119 pages) and wonderfully personal. He shares all the frustrations and embarrassments he and his wife suffered while looking for schools for their two young sons.

Petrilli started the project with an advantage. There are few people in the country as knowledgeable about schools as he is. He is executive vice president of the Thomas B. Fordham Institute, a Washington-based think tank focused on K-12 education policy, and executive editor of the journal Education Next. Thankfully he is a pundit unafraid of leg work, as proven by his intricate probe of state score results in Takoma Park, where he lived while writing the book.

Like many Washington couples, he and his wife wanted a school with a good mix of white and non-white kids from low-income and affluent families. That ruled out Wood Acres Elementary School in Bethesda, the least diverse school in Montgomery County. Its test scores were high but less than 1 percent of its students were low-income. Two percent were black and five percent Hispanic.

The usual rule is the higher the percentage of low-income children, who often start school behind, the lower the school’s average test scores. Petrilli discovered useful secrets in the subcategories available under the No Child Left Behind law to those who look for them. There were several schools near his home with a minority of white kids like his and many low-income children. They all had passing rates in reading above 90 percent, the result of an easy state test that made it hard to differentiate between schools.

So Petrilli looked at the percentage of white children at each school who not only passed but scored at the advanced level. Piney Branch Elementary, 33 percent low income, had a 73 percent advanced rate for white kids in reading. Pine Crest Elementary, 46 percent low income, had a 65 percent advanced rate. This was better than even less-than-1-percent-low-income Wood Acres, with a 62 percent advanced reading rate for whites.

Why? A K-2 school feeding kids into Piney Branch had a gifted and talented magnet program, Petrilli discovered. Pine Crest had a similar gifted program that drew high-scoring children from outside the neighborhood.

Researchers explained to Petrilli that if he and his wife picked a diverse school, no matter what its underreported advantages, he was going to get grief from friends and family. Only choosing a school full of affluent children would shut them up, family dynamics studies showed.

After a long search, he and his wife made a smart pick of a school they thought best for their boys, even though the choice conflicted with some of their stated values. I won’t spoil the ending. It is only one of many surprises in this remarkable book about the clash of school cultures and parental attitudes that has affected most of us, particularly those who live around here.