Sparkle (or Crystalline Reflection): This was a game that my students knew from language arts to practice spelling. I adapted it to fit a science classroom. I have the whole class stand up and I will ask students to spell out the answer to the question I pose. Going down the row of students, one at a time, each provides the next letter to spell the answer. If someone says the incorrect letter, they sit down and the next student restarts the word. Once the answer has been spelled out, the next student declares "sparkle" and the student after them has to sit down.
Last Scientist Standing: Similar to Sparkle, I pose a question to a student. If they know the answer, they stay standing and I give a new question to the next student. If the first student does not know the answer, they sit down and the question moves on to the next student. I don't repeat the questions so that all students have to pay attention.
Rock, Paper, Science: Students partner and listen for the trivia question. I count down from three and they shout the answer. If they are both right, they have a rematch. If they're both wrong, they sit down. If one student gets it right, they find a new partner and the student that missed it sits down.
My students have become so familiar with these games, that it requires little time to transition, but it did not require much explanation in the beginning either.