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RED OAK (CBSDFW.COM) – Parents of children at Eastridge Elementary School are concerned after students were assigned a study manual fraught with errors.

"It was kind of a fluke… I was just going through her folder," said parent Amy Hedtke, who noticed a mistake after her daughter received a grade of 100 despite answering incorrectly.

Other mistakes presented as fact were: Texas has 35 senators and 163 representatives in the legislature.

But there are 31 senators and 150 representatives in the state legislature.

"I knew because I've been working the Texas Legislature the last couple of sessions," said Hedtke.

She told her daughter's 4th grade teacher, who immediately pulled the study manual -- published by Gallopade International -- from her classroom.

Gallopade International bills itself as "an award-winning publisher of educational products for children and adults."

The publisher hasn't commented on the errors in its study manuals.

Hedtke and other parents are left wondering how many more mistakes are going unnoticed.

"I tend to be very concerned more for our teachers who are relying on these publishers to give them the right information so they can teach," said Hedtke. "You got a lot of different classes, a lot of different kids learning a lot of different subjects."

The assignment book was copyrighted 2006, which means students may have been taught incorrectly for the last nine years.

Red Oak ISD has pulled the assignment for good.

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