When Creating a Custom Assessment, you use your state standards to add Assessment Objectives for your test. Each Assessment Objective that you add contains 4 possible test items (questions). When you get to the create portion of the process it lets you name your test and select your characteristics. One of the Assessment Characteristics is for Assessment Length. It lets you choose between Standard and Shortest.
If you select Standard, Classworks uses all 4 of the questions available for each Assessment Objective added (Example: 10 objectives will give your students 40 questions).
However, Classworks uses an algorithm that adapts the assessment to how the student is performing. If a student gets the first two questions from an Assessment Objective right or wrong, it will not give them the remaining two questions. Classworks determines that if a student missed the first 2 questions of an objective that they likely need more help. Likewise, if a student gets the first two questions correct, they have a firm grasp on that objective and can move on.
So, in our example of creating a Custom Assessment with 10 objectives and choosing to create it using the Standard Assessment Length, students will see a minimum of 20 questions and a maximum of 40 based on their performance.