Having someone watch the instruction in progress provides a valuable perspective. Observations may be fairly formal, wherein specific behaviors are observed and recorded or perhaps even rated. Checklists or rating scales (see Chapter Seven) can be used. Observations may also be rather informal a colleague may sit in on a class or two and discuss what he noticed after the observation Generally, though, observations are most useful for obtaining de- tailed information on specific teaching behaviors and skills. They are time-consuming but yield meaningful and sometimes surprising information. Bear the following in mind when using observation as an evaluation tool