Ms. Thompson is a third-grade special education teacher. She recently taught a science unit on plants and prepares to give an end-of-the unit assessment on the topic that involves answering some multiple-choice questions and short responses. The final letter grade from this assessment will be used to select students for challenging science projects. Which of the following is the type of assessment the teacher is using?

Diagnostic assessments are utilized prior to instruction to gauge students' existing knowledge and skills, helping teachers identify areas that need focus. Ms. Thompson is not using this type of assessment, as her evaluation occurs after instruction has been completed, aiming to measure what students have learned rather than identify prior knowledge or skills.

Formative assessments are conducted during the learning process and provide ongoing feedback to improve student learning and instructional methods. While Ms. Thompson may have used formative assessments throughout her unit, the assessment described is not formative since it occurs at the end of the unit to determine overall achievement.

Norm-referenced assessments compare a student's performance against a group or norm. Although Ms. Thompson's assessment may yield scores that could be compared to a broader group, the primary purpose is to measure individual student mastery of the content rather than to rank students against each other, which is characteristic of norm-referenced assessments.