The early educational support of basic school skills during nursery can have a positive impact on a successful transition into primary school and future school success and achievement -- especially for in this context low-performing children. Therefore, most German nurseries developed additional concepts to support the acquisition of basic school skills during the last year of nursery. However, due to the COVID-19 shutdown face-to-face support for pre-schoolers was closed down. This study attempts to examine how basic school skills with respect to language and mathematical skills of pre-schoolers developed during the COVID-19 nursery shutdown. 49 children were evaluated in a single-group pre-post test design using five subtests of the Intelligence and Development Scales 2 (IDS-2) before and after nurseries were shut down. Additionally, qualitative interviews were conducted at t[subscript 2] to provide further reliable and valuable information that goes beyond structured testing. Research showed significant decreases of language and mathematical skills. These findings support the conclusion that nursery shutdowns may have a negative impact on pre-schoolers' educational skills which help to make transitions easier. Concludingly, the study stresses the particular role of nurseries with regard to early childhood education and childhood development in order to support the transition to school.