Abstract
Librarians teach in many different environments. It is often difficult to gauge whether students are benefiting from training. Students often feel self-conscious or uncomfortable asking and answering questions in class. Audience response systems (ARS) make it easy for presenters to get immediate feedback from students who have the ability respond anonymously. Web-based ARS allow participants to engage with presenters using their smartphones, tablets, or computers. This column explores four web-based ARS that are available for free or have free options.