Few questions regarding windows 7, server 2008 R2

1. How do people prevent students from being able to "search again in Computer, Custom & File Contents" been looking for it in group policy but it doesn't seem to exist.

2. We are using the classic start menu and theme and when students log on they get the control panel Icon how do people remove this.

3. Were in group policy can i stop network Showing up in windows explorer.