What is MY First Amendment?

The importance of the first amendment is dramatically important because of that it is a well known amendment. Although it has changed  thought when it was first introduced on June 8, 1789, the meaning on the first amendment and many others have changed. That is because of dramatic and horrifying events that occurred thought the centuries. Due to those events those rights have been adjusted today in the 21st century. One example that can clearly show the change of the first amendment is school rules and environment. At a public middle school or high school, the administration restrict the rights of students. First of all, schools throughout the country have created dress codes that prevents students from wearing what they want, preventing them from expressing themselves. The schools claim that they created those rules to prevent students from creating a bad environment, distracting classes, and to protect and provide safety for the rest of the school. From several cases I studied and looked more deeper into as I was doing my Law and Society project, I saw how the meaning of the first amendment, that people find the most important in society, has changed. A human cant be guaranteed to fully have the right to express or have the freedom of speech in a public school or transportation without  having someone file them as doing something wrong or inappropriate. Is the government violating our fist amendment because others had to ruin it and violated THEIR OWN rights? Is it our fault?