Different people have different handwriting styles, but on average, between three and four pages of handwriting fills a typed page if you use single spacing. If you use double spacing, of course, you get between one and two typed pages. Another factor that influences your outcome is whether you use college-ruled paper or wide-rule paper. College-ruled paper has more lines on it which means you fit more handwriting onto one page.
If your teacher asks you to turn in a paper of a certain number of pages, ask if the teacher also has a certain word count in mind. It is easy to track word count on a word processed document, and that way you are sure to write enough for the assignment.