I think open-ended questions are a good assessment strategy. I believe it is important to make sure that they are on the right track when answering the question and should be guided. These types of questions are good on a test because students are forced to think on their own. However, I think they should be covered during class before the test is given so students can be prepared and be able to find the answers before the test. A follow up needs to be done after the test as well to make sure students know the correct answers.
Mulitple choice is nothing more than being able to guess correctly.
It requires no depth of knowledge and hurts thoes with specifice learning disabilities. I would urge teacher to asses using essays, short-answer, and portfioios instead of multile choice. Sure it takes a little longer to grade, but it gives you a much better idea of what your students know. Multiple choice test require very little cognitive ability, compared to the alternatives. Teaching students to think for themselves is not done by having students regurgitate information in a mulitple choice setting.