I teach high school auto shop and here is an old ignition trainer that I use. It is the old point style ignition and I still use it because the theory is still the same. It used points, which is a simple switch to make or break current to a high voltage coil. Newer electronic systems do the same only they use solid state components instead of a mechanical switch. Students always struggle trying to understand that the spark happens when the power is removed from the coil not when power is applied..