My students add a new entry in their Morphology Dictionaries (can be purchased on TPT from Ladybug Teacher Files) every day. Then we choose one or two words from the examples list to put on the web. My Word Web is a long dry-erase board with words written on construction paper and held up by homemade magnets (Dollar Tree adhesive photo magnet sheets covered with colorful card stock - cut into squares on a cutting board).
The kids got really excited about choosing words to add and drawing the connections with other words on the web, so I let them pretty much take over the operation. It wasn't until a class visitor took a picture of the web and put it on Twitter that I realized it had become more of a word jungle. I fixed the connections and added labels to some of them.
Each word is connected with a colored line according to the key in the corner of the board.
The best thing about this wall is the discussions the kids end up having about words. They see words in their self-selected books and come up to ask me if the word fits with the root we studied. One girl asked me the other day why we have this wall. Before I could answer, three of her friends jumped in and explained it perfectly. "If you know these word pieces," one friend said, "then you can figure out what big words mean and use them in your writing."