Private company

CTB/McGraw-Hill

Publisher of educational assessment

DRC/CTB (CTB) was a publisher of educational assessment for the early learner, K–12, and adult basic education markets. DRC/CTB was a division of Data Recognition Corporation (DRC) until being fully merged into DRC's Educational Services division. From 1965 to 2015, the company was known as CTB/McGraw-Hill, a division of the McGraw-Hill companies, and prior to 1965 California Testing Bureau was an independent company.2 Wikipedia text CC BY-SA 4.0

Last updated Oct 20, 2026.

Overview

1926Founded1

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DRC/CTB (CTB) was a publisher of educational assessment for the early learner, K–12, and adult basic education markets. DRC/CTB was a division of Data Recognition Corporation (DRC) until being fully merged into DRC's Educational Services division. From 1965 to 2015, the company was known as CTB/McGraw-Hill, a division of the McGraw-Hill companies, and prior to 1965 California Testing Bureau was an independent company.2

The story

CTB was established in 1926 in Los Angeles by Ethel Clark. Clark's husband Willis had developed the Los Angeles Diagnostic Tests in the Fundamentals of Arithmetic, which she bought the rights to sell. She sent out 25 cent postcards advertising the availability of the test to various districts around the country. One year later, she heard from her first customer: the Kansas City school district. In 1960, the company relocated to Monterey, California, where the company headquarters was located until merged into DRC.

In 1965, CTB was acquired by McGraw-Hill Education and became CTB/McGraw-Hill.

On June 30, 2015 McGraw-Hill Education announced that Data Recognition Corporation (DRC) had agreed to acquire "key assets" of the CTB/McGraw-Hill assessment business.

From Wikipedia’s article on DRC/CTB, shared under CC BY-SA 4.0.3

Timeline

  1. 1926Founded Founded in Los Angeles1

Sources

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