Journalists from "ZAXID.NET" spoke with Olena Vanieieva, Corresponding Member of the NAS of Ukraine, the leading researcher of the Institute of Mathematics of the NAS of Ukraine about the reasons for the deterioration of the level of mathematical literacy among schoolchildren in Ukraine. During the full-scale war, mathematics is a mandatory subject in the National Multi-Subject Test, and many teenagers cannot cope with the testing. For example, in 2025, every eighth participant of the NMT did not pass the mathematics threshold, demonstrating knowledge worse than the 5th-7th grade level. Mathematics is necessary for the development of critical thinking, STEM specialties, for the development of technologies during the war, and for the reconstruction of the country in the future.