One of the changes I made this year is I stopped giving end of unit/chapter tests. Our school is using Achievement Network to administer benchmark exams every 6 weeks and we have arranged our curriculum so that we are teaching those standards that they will be tested on. So I thought, these are actually the unit tests, there is no need for two.
What I do give are frequent concept checks. These are quizzes and I've made them worth 60% of the students grade and I hoped that by now students would get the idea that since they can be retaken as many times as needed, they would look at the mistakes they are making and fix them, study more to pass the second or even third try. I've taught them this and copied this (I think from Sarah at Math=Love or Sarah at Everybody's a Genius) bulletin board that has been up since September which I refer to constantly.
What frustrates me the most are the students who wait until the end of the marking period to retake them and I don't think they've even given one thought to the concepts they are being retested on. I'm not sure what to do at this point. I've tried having them fill out a retake form and get it signed by their parents, but that resulted in a lot of paperwork to keep track of with no results to show for it.
I do want to add that since I've been running my class as a flipped classroom, my last two concept checks have only had 2-3 kids not passing! So that makes my frustration a little more manageable!