The purpose of this research was 1) to develop a new instrument to explore factors parents value regarding informal science, technology, engineering, and mathematics (STEM) enrichment experiences for their children in Illinois, and 2) to adapt and use an existing instrument to assess the degree to which parental perceptions of their child’s STEM attitudes and beliefs align with the child’s actual STEM attitudes and beliefs. A quantitative cross-sectional survey design was implemented over two parts. During Part I, a new survey was developed to quantitatively measure the degree to which certain factors are valued by parents when considering STEM enrichment programs for their child(ren). Part II studied the same population of parents using an adapted version of Friday Institute’s (2012) S-STEM survey which is a reliable and valid survey that measures student STEM attitudes and beliefs. Parent perceptions of their child(ren)’s STEM attitudes were determined using the adapted tool (PPS-STEM) and the student's actual STEM attitudes were measured for children of the parent participants using the original S-STEM instrument. A quantitative comparison of parent and child survey responses determined the degree to which these survey responses were aligned. The results showed that parents rate STEM enrichment program factors differentially. Some STEM program characteristics, such as program topic and timing of the program, were rated more highly than others, such as the extra's provided and whether outdoor activities are incorporated. Furthermore, parental perceptions of student STEM beliefs aligned well with the student’s actual STEM beliefs. This study can inform STEM enrichment programs about parental perceptions that affect program enrollment decisions they make for their children, which could inform national informal STEM education initiatives. Keywords: STEM, informal STEM, out-of-school time STEM, STEM enrichment, Parent Perceptions, Student STEM beliefs, STEM Education