WASL - Washington Assessment of Student Learning. Tests under this heading were given to public school students from 1997 through the spring of 2009 in an attempt to determine whether they were meeting the state's grade level expectations. The test was used as part of the Bush Administration's No Child Left Behind Act.
Unfortunately, more children ended up being left behind during this period - with the state dropout rate climbing to more than 19 percent. Some ethnic/racial groups saw nearly half of their children leave school without graduating - unable to pass the minimum requirements under these tests. The WASL is being replaced in the 2009/2010 school year by the:

MSP - Measurements of Student Progress. Specific details of the tests have not been released. So far we know that they, 1) won't take as long as the WASL did, 2) will be administered to 3rd-thru-8th graders and, 3) will go on line in the next two years.
In describing the test, the OSPI (another acronym - Office of Superintendent of Public Instruction) Web site says, "State testing should never be the sole judge of a student's academic skills and knowledge. A student's entire performance should always be considered."
The website fails to explain how that is going to be accomplished. High schoolers will be given the:

HSPE - High School Proficiency Exam. This is another test aimed at measuring a student's proficiency in basic skills.
The class of 2013 will be the first required to pass all components of the test: reading , writing, math and science. Students slated to graduate before that (in classes 2010, 2011 & 2012) will only need to pass the reading and writing components.
All of the tests help determine a school's:

AYP - Adequate Yearly Progress. Under NCLB (No Child Left Behind), a year-to-year measurement of student achievement levels is calculated on a school by school basis based on the scores students at each school obtain on the WASL.
One potential stumbling block of the plan is that, by definition, every year the state must "raise the bar" so that by the 2013/14 school year 100% of the state's students will achieve proficiency in each subject area. Last year 628 Washington schools failed to show adequate yearly progress. 64 of them were in what is described as "step 5" - which requires some degree of restructuring to try to improve the achievement of their students.

We'll be watching Friday morning as the latest figures are released... and will try to break down the results for you, without the acronyms.