Adolescents from low-income households are at increased risk of growth failures due to inadequate food intake. This cross-sectional study assessed dietary practices and nutritional status according to FANTA measurement standards. Among 610 randomly selected adolescents attending public primary schools in rural and semi-urban Kuyu district. Dietary diversity and anthropometric measurements (height, weight, and Body Mass Index) were collected and analysed using SPSS version 26 and WHO Anthro Plus software. The study population included 36% females and 69% semi-urban residents. Dietary analysis revealed that most adolescents consumed two or fewer daily meals, primarily cereals and legumes. Over 90% of the households consumed less than four food groups during the 7-day recall period. The anthropometric assessment showed significant undernutrition: 19% of early adolescent girls and 34% of late adolescent boys were underweight; 27.5% were stunted; 8% and 5.9% had moderate and severe undernutrition, respectively; and 13.8% exhibited thinness, with boys more affected (35%) than girls (10%). Additionally, 7% were overweight, and 64% presented single, double, or triple growth failures. Regression analysis showed that Children in female-headed households had 1.7 times higher odds of stunting, adolescent girls had 1.8 times higher odds of thinness, late adolescents had 70% lower odds of being overweight, and adolescents from households with off-farm activities had 4.5 times higher odds of being overweight. Inadequate meal frequency and limited dietary diversity contribute to the high prevalence of undernutrition among Kuyu district adolescents. A school feeding programme is strongly recommended.