GeoGebra Ambassador 2021/22. I am a co-founder and chairman of the Swedish GeoGebra Institute. Together with Thomas Lingefjärd I have written a book about mathematical modelling with GeoGebra, written several articles about GeoGebera in the Swedish mathematics teachers journal "Nämnaren". I am currently the lead translator for Swedish and maintains the local institute's web site. I am also responsible for providing the Swedish support through our Facebook support group, "GeoGebrasupport på svenska". I am also co-author of "Mathematical Modeling: Applications with GeoGebra", by Wiley, 2017 http://eu.wiley.com/WileyCDA/WileyTitle/productCd-1119102723.html. For a living, I am a lead teacher in Sweden, using GeoGebra almost every lesson and teaching the students how to use it as their tool of choise. I am especially interested in problem solving and modelling with GeoGebra. https://geogebra.se/ jonas.hall@norrtalje.se https://www.facebook.com/jonas.hall.963