This paper analyses the relationship between inadequate housing and the school performance of children from poor Czech households. It shows that children (ages 7–12) from low-income households (defined as those with up to 2.4 times the minimum living income) have higher chances of serious problems in school performance if they live in unstable or nonresidential housing. The effects of housing instability and non-residential housing among children from low-income households are significant and substantial even when controlling for parents’ educational attainment and labour activity, family structure (e.g. single parent etc.), household size, and the child’s age. The effects of other housing problems are significant only in their extreme forms (overcrowdedness) or when combined with other housing problems (the housing cost burden). These findings are used to examine whether the Czech Social Housing Act currently under discussion is needed to help poor families with children and whether it has adequately defined its target group if it is to protect Czech children from the negative effects of inadequate housing.