Hannula, M.S., Haataja, E., Laine, A., Portaankorva-Koivisto, P. and Moreno-Esteva, E.G. 2019. Editorial. LUMAT: International Journal on Math, Science and Technology Education. 7, 2 (Oct. 2019), 5–8. DOI:https://doi.org/10.31129/LUMAT.7.2.426.