Most students will understand and respect your rules if you explain the rationale behind them. Email - Get an email account for your class. Keep class email separate from your personal email. There may even be some parents that will correspond with your students from the business world. Have students publish their results as a series of Web pages.
Some projects are commercial and require a registration fee, but most are totally free of charge.
Global SchoolNet maintains a registry of projects, and Judi Harris has classified Internet Projects into many genres. Her site has lots of examples of projects that you can design and implement yourself. You can do it. Give it try. Make the Internet part of your class.