Cognitive dysfunction is a core symptom of schizophrenia and the most accurate predictor of clinical outcome. Unfortunately, current treatments cannot improve cognitive deficits, resulting in a need for deeper understanding of the disease's pathogenesis. Dendritic spines are intimately linked to cognition, with strong evidence that spine plasticity is impaired in the schizophrenic brain. Mouse models can provide unprecedented insight into how genetic factors influence cognition via regulation of spine plasticity. Here, we review the cognitive and spine data of several prominent genetic mouse models of schizophrenia risk genes.