These are lecture notes for five sessions in the AMSI Winter School on Computational Modelling of Heterogeneous Media held at QUT in July 2019 [https://ws.amsi.org.au/]. Aim: Discuss a mix of new mathematical approaches for multiscale modelling, heterogeneous material in particular, along with corresponding novel computational techniques and issues. I include discussion of a developing toolbox that empowers you to implement effective multiscale 'equation-free' computation [https://github.com/uoa1184615/EquationFreeGit.git].Pre-requisites undergraduate ordinary and partial differential equations, state space, trajectories, stability, bifurcations, power series solutions, separation of variables, eigen-problems and Sturm-Liouville theory; basic numerical methods for time integration of ODEs and for spatial discretisation PDEs, some perturbation methodology.Pre-reading recommend the review article by Kevrekidis & Samaey (2009). Perhaps also get an idea of centre manifolds [https://en.wikipedia.org/wiki/Center_manifold].Activities sprinkled are some small activities for you.