Many college students seem to find it impossible to resist the temptation to text on electronic devices during class lectures and discussions. One common response of college professors is to yield to the inevitable and try to ignore student texting. However, research indicates that because of limited cognitive capacities, even simple texting can reduce comprehension of class material at a rate of 10-20%. We review that research and present our study of the effects of texting on comprehension. Proposed alternatives to ignoring texting or outright bans include using smartphones for classroom exercises, educating students about the dangers of multitasking, and the use of "technology breaks."