Without knowing what school you attended I can't give you specific suggestions for places to search.
Your first step should be contacting either the school you attended to see if it has a records department or if a faculty member has information on your teacher. You can also contact your school district's main office and ask for a records or archive department.
Beyond contacting the school, you can try a website like Classmates. Another option is to create a Facebook account to see if your school, or any of your former classmates have posted information about your class.
Hopefully this gives you some ideas for how to go about searching. Best of luck!