I use QUIZLET for the students.  They get a pre-printed list of terms and their definitions at the beginning of the unit.   One day I didn't get their vocabulary quiz printed out, so they all whipped out their phones for me and did one of the online quizzes.  Those that had used the games and puzzles to study did great and those that hadn't didn't.  After that, they ALL learned to use the app to study and they improved.

Here's the 2nd attachment.

I love this question! I, too, struggle with the best way to handle vocab. I'm attaching two approaches that I've used. The first is a running vocab document, where I tell students the most important words from each unit and have them fill it out throughout the year. The second is an activity I do specifically for the solutions unit, before I've taught any vocabulary. I find that forcing students to use the terms when the don't necessarily know them makes for funny stories, but more importantly makes the actual definitions "stick" once they are presented. Cheers!

Here is the other one

One of the ways I approach vocabulary, and reading the book in general, is with a method called VCEE. Vocabulary, Concepts, Evidence & Examples. You break down a chapter or a section of the reading into the Vocabulary words that the students must either define in their own words or use in a sentence that makes sense. Then have the students pick out the key concepts, or give them the key concepts and have the students relate them to pictures from the text. And then there is evidence and examples, which are related to the key concepts. I have attached 2 examples that I use. One is based on the Holt Chemistry, chapter 2 and the other is for my AP class, based on Brown Chapter 15, equiliblium