McGraw-Hill Education has acquired Engrade for an undisclosed amount.

New York-based Engrade develops a digital platform for K-12 education that provides data, curriculum and tools for educators

McGraw-Hill Education was acquired by Apollo Global Management LLC (NYSE: APO) in March 2013. 

The company has made several recent acquisitions. In June, the company bought Aleks Corp., which develops adaptive learning technology. In January, McGraw-Hill Education bought a 20 percent stake in Area9 Aps, which also develops adaptive-learning technology.