This chapter takes 118 communities in Shuangliu District, Chengdu, as an example and uses a eXtreme Gradient Boosting (XGBoost) model to explore the non-linear effects and threshold effects of children’s daily travel distance on their travel mode choices by considering different destinations of children’s daily travel in the communities. We found that children’s daily travel distances and destinations are vital for their travel mode choice, especially the most significant effect of travel distance. For different children’s daily travel destinations, travel distance has a more substantial threshold effect on children’s non-walking travel mode choice. Therefore, to scientifically and rationally distribute child-friendly facilities in the community, which may help children’s healthy development, a child-friendly city should be planned, constructed, or renewed through the internal logical relationship between children’s daily travel destinations, travel distances, and travel mode choices should be considered comprehensively.