PLATTEVILLE — Teachers sometimes try to combine more than one subject area in a lesson, to show how two subjects can be connected.

Two Westview Elementary School third-graders did some connecting of their own when they discovered a math error in a social studies book.

In January, Connor Timlin and Collin Bradley were reading I Grew Up to Be President, written by Laurie Calkhoven, in teacher Sally Woodworth’s class. Seeing their interest, Westview teacher Scott Woodworth, who has an interest in presidential history, challenged Connor to memorize all the presidents in order.

While reading, said Connor, “I found a mistake and I told Mrs. Woodworth.”

The mistake was in the page on Lyndon B. Johnson, listed not as the 36th president, but as the 43rd president. George W. Bush, like Johnson from Texas, was the 43rd president.

“Connor went and told me, so we told Mrs. Woodworth, and Mrs. Woodworth got on the computer and emailed the author,” said Collin.

“Connor was doing what good readers do — really thinking about text and asking questions, especially when something isn’t right,” said Sally Woodworth. “I found the website for the author and the boys and I sent her an email stating Connor’s concern about the error. We were very surprised and happy when she responded.

“She said she would copy the email to her editor and the mistake would be corrected in the next printing of the book — which could take some time.”

“Some time” turned out to be about four months. The sharp-eyed third-graders were at the Westview Scholastic Book Fair May 12 when they found I Grew Up to Be President, but with Johnson listed as the 36th president.

Two days later, Woodworth’s mailbox contained an autographed copy of the corrected edition.

“As promised, I’ve enclosed a corrected edition of I Grew Up to Be President with Lyndon Johnson now correctly identified,” wrote Calkhoven. “It’s wonderful to hear from readers — even when they’re pointing out a mistake!”