This article reports Phase I results of a questionnaire study on the perceptions of US teachers and parents on the cognitive functioning of children with severe mental disability and children with congenital deafblindness, ages 4-12 years. Teachers were more likely than parents to report emerging skills and to provide examples of how the skill was being taught. Teachers and parents of children with severe mental disability had different perceptions about how children demonstrated understanding of cause-effect, object permanence, memory, incidental cues, reasoning and creativity. Teachers and parents of children with congenital deafblindness differed in their perceptions of how children demonstrate understanding of incidental cues and exhibit reasoning. Both teachers and parents expressed concern about whether choice making was meaningful. Novelty was reported to be a motivating factor for children with severe mental disability, while familiarity was cited as motivating for children with congenital deafblindness. Teachers and parents of all children cited consistency, routine and repetition as important to learning.