Blooket - https://www.blooket.com/
GimKit - https://www.gimkit.com/
Kahoot -
Teacher Site: https://getkahoot.com/
Student Site: https://kahoot.it/#/
Socrative - https://socrative.com
Quizizz - https://quizizz.com/
FlipQuiz - https://flipquiz.me/
PurposeGames - https://www.purposegames.com/
(quiz through gaming)
Riddle - http://www.riddle.com/welcome
QuizBean - https://quizbean.com/
Testmoz - https://testmoz.com/#home
ClassTools.Net - http://www.classtools.net/
Jeopardy Labs - https://jeopardylabs.com/
Quizlet - https://quizlet.com/