This is an AWESOME way for students to make connections between vocabulary words. Students are allowed to think creatively, as there is no "one right answer." They will think deeply about their vocabulary words, and go just beyond spitting back definitions.
Students cut out the dominoes, lay them end-to-end, and have to explain the connections between the words. They can write the connections or explain them to you in a "conference"- whatever you prefer.
This set has 18 dominoes with two biochemistry-related vocabulary words on each domino (parts of an atom, macromolecules, enzymes, Gibbs Free Energy, properties of water, bonds, and a couple "word of your choice" spaces).
Even though these words are biochemistry-related and geared towards AP Biology students, the words on the dominoes can be changed for any grade level and any class. The PowerPoint slides can be modified over and over again to incorporate new words!
At my school, we have 45-minute class periods. It took some students 45 minutes, and others took some time working into the next school day. I would estimate that this activity takes about an hour (and plan for more time if you want to conference with students/talk with them about their connections, not just read what they wrote).