This study investigated middle school students' beliefs about intelligence and differences in the development of intelligence across ages, beliefs about giftedness and the development of giftedness, and how beliefs about intelligence and giftedness were related. A total of 52 eighth graders from two regular classes (n = 36) and one gifted class (n = 16) at a public school in the U.S. Midwest completed a survey and a vignettes task. Results revealed that participants associated intelligence with school and non-school intelligence, knowledge and learning, smartness, and motivation. They associated academic giftedness with intelligence, motivation, school achievement, and high ability. Participants were more certain young children could grow intelligence. Most participants endorsed incremental views of intelligence and giftedness. This was more evident in students holding an incremental belief about intelligence, and in non-gifted students. Gifted participants and those holding an incremental belief about intelligence placed more value on motivation and learning. Theoretical and practical implications were discussed.