This paper is part of a broader study which explores South African pre-service teachers' use of the jump strategy on the empty number line for enhancing their confidence to do and teach mental mathematics computation strategies. The focus of this paper is the use of micro-teaching in the form of video recordings by pre-service teachers. Forty videos were analysed thematically indicating that most pre-service teachers could implement the strategy with some level of fidelity. Three micro-teaching videos are shared in this paper to exemplify the range of strong, medium, and poor implementation fidelity.