Abstract
The rapid growth in the number of children with special educational needs places increasing pressure on the institutional capacity of education systems, and the timeliness of coverage responses to changes in the target group has become a central concern for quality education and reducing inequalities. Formal expansion of inclusive Education is often not matched by a proportional adaptation of infrastructure, staffing, and financing, making the effectiveness of institutional management difficult to measure. This study examines the institutional adaptation of Kazakhstan's inclusive education system to changes in the target group size and the temporal structure of the demand–coverage relationship. The study employs annual official time-series data for 2011–2025 on the number of children with special educational needs and the share of children with disabilities covered by individual educational programmes, applying dynamic analysis, compound annual growth rates, elasticity coefficients, segmented regression with a structural-break dummy variable and lagged correlation, and proposes an Institutional Adaptation Index (IIA). The results show that the IIA declined from 100% in 2011 to 53.3% in 2023 while the uncovered share of the target group rose from 44.7% to 62.8%; in 2024–2025 the index recovered to 88.8% and 94.4%, the uncovered share fell to 17.6%, the structural break is significant (R² = 0.970; F = 159.20; p < 0.001), and the strongest association appears at a two-year lag (r = 0.827; p < 0.001). The findings suggest that the system moved from a prolonged accumulation of a relative institutional gap to its accelerated reduction, with a delayed response characteristic of strong institutions emerging after a lag.