SEATTLE — Washington state is tops in the nation for something many students, educators and parents would like to change — the number of tests required to earn a high school diploma.Starting with this year’s sophomores, Washington will be the only state to require students to pass five different tests to graduate. Nine states have four graduation exams. Four states have three such tests. Ten states have one or two. In 26 states, high school students don’t have to pass any exams to graduate.Every state has to test its students in reading and math, but they get to decide whether to use those tests as a graduation requirement and whether to add other subjects like writing and science to the mix, as Washington has.Superintendent of Public Instruction Randy Dorn would like to see Washington save money and time by dropping down to three graduation exams and by transferring most grading of a test alternative known as the “collection of evidence” to local school districts.House Bill 1450, which would make these changes, is scheduled to be heard today in the House Education Committee. Dorn said the bottom line is: Are students learning more in Washington because they have to take high school exit exams?