Pearson's book, American Government, implied the country's legal system was based upon the Ten Commandments.
According to The Telegraph, a passage in the book claims that:"Moses helped establish a legal system, including the Ten Commandments, to govern his people.
"Similarly, the founders of the United States wrote the constitution and established a system of law to govern Americans.
"They were also part of a tradition that recognised the Ten Commandments as a guide for moral behaviour."
Campaigners argue that the relationship has been exaggerated and gives the wrong impression to students.
The Texan Freedom Network Education Fund, which lobbies in relation to religious education, reportedly claims: "The legal system that Moses founded had theocratic elements, which made it very different from the republican system of law the Founders established.
"Similarly, the text neglects to mention that the Founders were reacting against several of the crucial elements of the moral, legal, and political tradition associated with Moses and the Ten Commandments."
In a statement, Pearson said: "Pearson works diligently to ensure its instructional materials are compliant with Texas standards.
"We are reviewing the TFN report and are listening to all interested stakeholders as we enter the public hearing process."