Studies of driving indicate that the conversational aspects of using cell phones generate high risks from divided attention. Prior surveys document high rates at which students carry phones to and use them during class. Some experiments have demonstrated that cell phones distract students from learning. The present studies combined survey and experimental methods to determine student expectations about and actual performance under cell phone use conditions. On the survey, students estimated the number of questions they could answer out of 10 when texting and when not texting. For the experiment, we used a repeated measures design with simulated classroom presentations and measured performance on a 10-item quiz. Students expected to lose close to 30% on a quiz and actually did lose close to 30% when texting. We discuss implications of our methodology and our findings for improving student learning. (Contains 1 table.)