Some homeschooling families use standardized tests like the Iowa Tests of Basic Skills (ITBS), Stanford Achievement Test (SAT), or TerraNova, primarily for evaluating progress and comparing their child's performance to national averages. These are often optional.
Other families rely on portfolio assessments, narrative reports, observation, and projects to gauge their child's learning. They might use end-of-unit tests provided with their curriculum, but these are usually formative assessments designed to reinforce learning rather than formal examinations.
Still others might use a combination of approaches. Some states require homeschoolers to take standardized tests or other assessments to demonstrate their child's progress, but the specifics vary widely by location.
In short, there's no single answer. The use of exams in homeschooling is highly variable and depends on individual circumstances and choices.