<![CDATA[Biology instruction on animal classification at SMA Negeri 7 Bengkulu Utara remained dominated by lecture and note-taking, with worksheets consisting of conventional exercises that gave students little opportunity for active engagement. Observation of 32 grade X students found that around 78% were passive during lessons, 72% reported difficulty understanding animal classification, and the mean daily test score reached only 6.8 against a minimum criterion of 7.5. This study aimed to produce a Word Square Student Worksheet (LKS) on animal classification that is valid and practical for fostering the conceptual understanding of grade X students. The research used a research and development design following the 4D model of define, design, develop, and disseminate, limited in practice to the develop stage. Data were collected in May–June 2026 through content-, media-, and language-expert validation sheets and teacher and student response questionnaires, and were analysed descriptively as percentages. Twelve students took part in the small-group trial and thirty-four in the limited-group trial. Validation reached 67.69% from the content expert, 74.29% from the media expert, and 94.64% from the language expert, with an overall mean of 78.87% in the valid category. Practicality reached 95.3% from teacher responses and 90% from student responses, both highly practical. The worksheet is therefore suitable as an alternative teaching material in Biology, since it creates active and enjoyable learning, helps students recall scientific terms, and fosters conceptual understanding of animal classification.]]>
