As an adult education ESL teacher, I teach a government unit every term. This helps English learners to understand how Americans think about freedoms, laws, leaders, and police.
My advanced class learns about the Constitution and the First Amendment rights of religion, speech, press, assembly and petition. The concept "of the people, by the people and for the people" is usually well received. I demonstrate the freedom of speech by speaking poorly of the current president and showing no fear of reprisal. This is always startling for those from countries where speech and the press have no freedom. Freedom of religion/no religion is usually greeted with mixed reactions. Freedom of the press is always creates a heated discussion. I have taught journalists who were unable to live in their country because of exposing corruption.
We also discuss the rule of law and that it applies to all people regardless of position or power. Impeachment comes up occasionally. When South Korean impeached their president my students were very shocked.
We learn about the three Branches of Government, their power and limits, balance of power, and term limits. These are often new ideas for many students. Many democratic countries around the world lack the balance of power and term limits. These countries often turn into dictatorships.
If possible, I teach about the different forms of government throughout the world and have students explain their country's government system. This is always prefaced with a discussion of respecting others' opinions and beliefs.
I have also had students participate in a mock Senate. Small groups have to draft and present laws. Then we have a short debate and vote. This exercise is very challenging for advanced students.
No matter what level of ESL you teach, you can always present government ideas. Literacy and beginning levels can learn about the flag, Constitution, and 3 Branches. Intermediate students can go into more even more depth and include voting. Holidays like Thanksgiving and President's Day can also be used to teach government and U.S. history. I usually teach about Washington and Lincoln/Civil War.
Lastly, to bring government down to a more practical level, I often invite a police officer to come into class to talk. For many students this is terrifying because of experiences in their native country. Listening to an officer speak about working in the community is an eye opening revelation for many.