Penmanship is the technique of writing something by hand. If your penmanship is terrible, you might want to type your book report instead.
Penmanship is a somewhat old-fashioned way to say "handwriting." Before typewriters and then computer keyboards were commonly used, teaching students tidy penmanship was considered to be extremely important. If you attended school in the 19th century, you would have spent hours practicing your penmanship in copy books, writing and rewriting the same sentences. Penmanship comes from the now-obsolete penman or "clerk."