Perhaps it would help if you had read the entire article and not just jumped in with a knee-jerk reaction to the word "Islam".
from the OP link:
"
“This is a world history class,” Simpson explained. “We are not teaching religion. Part of those world history studies involves the economics of a region and part of that is the religion which relates to the economy of that part of the world. In the Middle East, Islam is the only religion and it contributes greatly to the economics of the region.
In the overall scope of things, she said, Christianity is taught in segments about the reformation in Europe, along with Hinduism and Buddism.
“At some point we do comparative religion,” she said. “Religion is a big part of world history.”
Charles County Public Schools issued a letter to parents explaining their stance:
"Charles County Public Schools (CCPS) social studies curriculum adheres to the Maryland World History curricular standards that are a requirement for all counties in the state. These standards include an analysis of the elements of culture such as art, music, religion, government, social structure, education, beliefs and customs in societies throughout history. Regarding the study of history specifically, the standards also state that students should be able to analyze the customs and beliefs of world religions and their expansion, as well as how their establishment has impacted other areas of culture, and in certain times and regions, even caused conflict.
"The particular unit in question at La Plata High School is on the formation of Middle Eastern empires in which students learned the basic concepts of the Islamic faith and how it, along with politics, culture, economics and geography, contributed to the development of the Middle East. Other religions are introduced when they influence or impact a particular historical era or geographic region. For example, when reviewing the Renaissance and Reformation, students study the concepts and role of Christianity. When learning about the development of China and India, students examine Hinduism and Buddhism."