This puzzle is a great review of oxidation/reduction, voltaic cells, and general terms related to redox reactions. There is both a full color and a black and white option along with answer keys. Triominos are great in small groups as students must work together to match and complete the puzzle. Or, students can work independently, cutting and gluing the puzzle pieces. Try them in centers where each station has a different topic.
To save time, many teachers will pre-cut several sets on card stock which can be used year after year.
You can quickly grade for correctness by scanning the large letters on your answer key vs the students submitted or glued answers.