When in 2014 the STEM Career Interest Survey (STEM-CIS) was developed, the researchers could check this instrument with other target audiences. Also, the question remained if the instrument was applicable for both boys and girls. This article describes the development and validation of a Dutch language version of it, called the STEM-LIT instrument, an instrument to measure the interest of children aged between ten and 12 years in Science, Technology, Engineering and Mathematics (STEM), focusing specifically on children from families with low socio-economic status (SES). The instrument has been adapted and developed in five stages and tested among Dutch primary school pupils in groups seven and eight (ages 10–11 and 11–12). The instrument was first tested in two pilot studies, after which some amendments were made. The final version of the instrument was tested with 212 pupils, with a Cronbach’s Alpha of.91, adding supporting evidence to the reliability of the original STEM-CIS instrument and showing that the test is as reliable for both girls and boys.