Workbooks in the American education system, are cheap, paperback textbooks, issued to students. Workbooks are usually filled with practice problems, where the answers can be written directly in the book.

Workbooks are often used in schools for younger students, either in middle school or elementary school. They are favored because students can work directly in their books, eliminating the need for looseleaf and copying questions from a textbook. In industry, they may be customized interactive manuals which are used to help provide structure to an otherwise complex problem.

Workbooks also hold an advantage because they are usually smaller and lighter than textbooks, which equates to less trouble when the student brings the book home to complete their homework.

The term workbook is also used to describe other compilations of questions that require the reader to complete scratch-work when dealing with higher-level mathematics. It can also be used as a training tool for certain job positions.

More recently, electronic workbooks have permitted interactive and customized learning. Such workbooks may be used on computers, laptops, PDA's, and may be web-based.

Robert Arthur “Bob” Mould (born October 16, 1960) is an American musician, principally known for his work as guitarist, vocalist and songwriter for alternative rock bands Hüsker Dü in the 1980s and Sugar in the 1990s.

Born in Malone, New York, Mould lived in several places, including the Minneapolis-St. Paul area where he then attended Macalester College. There, he formed Hüsker Dü in the late 1970s, with drummer/singer Grant Hart and bass guitarist Greg Norton.

Hüsker Dü first gained notice as a punk rock group with a series of recordings on the independent label SST Records. One of the first 1980s underground bands to sign a contract with a major record label (Warner Bros. Records), Hüsker Dü found only moderate commercial success, but were later often cited as one of the key influences on 1990s alternative rock.

In the late 1980s, Hüsker Dü broke up acrimoniously amid members' drug abuse and personal problems. Mould and Grant Hart, the band's other songwriter and vocalist, still take occasional jabs at each other in the press, though the two revisited their Hüsker Dü back catalog together at a 2004 benefit concert for an ailing friend, the late Karl Mueller of Soul Asylum.