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STEM education programs are often formulated with a "hands-on activities" focus across a wide array of topics from robotics to rockets to ecology. Traditionally, the impact of these programs is based on surveys of youth on program-specific experiences or the youths’ interest and impressions of science in general. In this manuscript, we offer a new approach to analyzing science programming design and youth participant impact. The conceptual framework discussed here concentrates on the organization and analysis of common learning activities and instructional strategies. We establish instrument validity and reliability through an analysis of validity threats and pilot study results. We conclude by using this instrument in an example analysis of a STEM education program. 

Metal–halide perovskites are promising candidates to advance optoelectronic devices but are known to suffer from rapid material degradation. Here we demonstrate that nanoconfinement is an effective strategy for the long-term stabilization of metal–halide perovskite MAPbI 3 crystals against humidity-induced degradation and temperature-induced polymorph transitions. Two-dimensional X-ray diffraction patterns of MAPbI 3 films reveal an unprecedented air-stability of up to 594 days in non-chemically modified, non-passivated MAPbI 3 films deposited on substrates imposing complete 2D confinement on the tens of nanometers length scale. Temperature-dependent X-ray diffraction analysis and optical spectroscopy further reveal the suppression of temperature-dependent phase transitions in nanoconfined MAPbI 3 crystals. Most notably, the high-temperature cubic phase of MAPbI 3 , typically stable at temperatures above 327 K, remains present until a temperature of 170 K when the perovskite crystals are nanoconfined within the 100 nm diameter pores of anodized aluminum oxide templates. Photoluminescence mapping confirms that nanoconfined MAPbI 3 crystals exhibit spatial uniformity on the tens of microns length scale, suggesting that nanoconfinement is an effective strategy for the formation of high-quality, stable MAPbI 3 crystals across large areas.