There are many very basic plugins to slap up a poll or a survey, maybe even a quiz. If you are looking for something sophisticated you might have to turn to an online service, accessed through a plugin interface.
The main problem with using services that are tied into plugins is that they legitimize taking and using your data. This is a good enough reason to stay away from such polling services as PollDaddy, 4Q Survey, SurveyGizmo, and SodaHead. There are a few good free ones though.
Surveys Extended Download
This is a simple survey creator with everything you need to run multiple surveys and to analyze the data in different ways. It is really quite a pleasure to use.
The company dcoda is consolidating their PollMe, SurveyMe, and QuizMe plugins into their ContactMe plugin. It was annoying that when the plugin was installed it indicated there were forms created that needed to be imported. When approving the import, hundreds of extra forms appeared that were empty. Trying to delete them was futile, since you can only select one at a time. The fact that this occurred and that there was no way to mark all, reveals a lack of foresight. I would not even bother with this plugin after our brief experience.
This looks like a good idea. But when we tested it by making a new exam and hit save, it threw us to a 404 page not found error. So it is incomplete and I fear that this was on purpose to tantalize people into buying one of the two paid versions from their website. It is a dead plugin. Ignore this one or suffer struggling with it.
mTouch Quiz Download
This is a plugin designed to make it very simple for the user to take a quiz on a touch device, such as a phone. The resulting interface is very pleasant and simple to interact with. Getting a quiz up fast is quite easy.
This is really one of the most basic quiz plugins. It might be too bare bones, though. Just try it and see. There is a difference between easy and sparse, and this one is simply sparse.
While this fits the bill for basic quizzes, there are limitations. Answers are automatically shown at the end, with the answers. You might not want that, but Quizzin will not allow you to customize it.
Quiz Master Download
This one is a bit more than bare bones. There are enough options to make this a viable possibility for administering quizzes.
WP Survey And Quiz Tool Download
Here is the standard in surveys, polls, and quizzes in WP. It is the most used plugin for this category, so you can be sure it works well and is sufficient for most needs. You can place constraints that prohibit any one IP from submitting more than once.
You can take advantage of CSS and create templates to control the appearance of WP-Polls. Unfortunately, you must edit your WP theme files. So if you are uncomfortable with that, move on. There are also problems in Internet Explorer that you must fix by editing a line in a CSS file that belongs to WP-Polls. How ridiculous is this!
Pinnion Plugin Download
This is a service accessed through their plugin. While there is a free version and it covers all of the good stuff, you cannot be certain it will always remain free. They swear it will, but these things change with the wind. Meanwhile, you can just sit back and enjoy it while it lasts. They do have an export feature. So if they start charging you could export to CSV or Excel and import to another plugin, assuming the other one has an import feature.
This category of plugins has such a variety of quality and features from one plugin to the next that you would do best to just try the ones that were not complete failures in our tests above. See which one suits your needs.
ContactMe and Watu were complete failures. Hexam was too simplistic. Quizzin is too limited. WP-Polls is too complicated, editing files. Pinnion is a service, which is risky. So we recommend Surveys Extended, mTouch Quiz, Quiz Master, or the good old standard WP Survey And Quiz Tool. Obviously, this category really needs a lot more development by talented programmers and graphics artists. Four good plugins out of ten is a poor ratio. We hope there will be richer plugins in this category that are not tied into some service, whether or not paid.