Remember kids, baking is all about precise measurements. Professional bakers use weight instead of volume measurements in order to increase the accuracy of every measurement. You can also calibrate your oven using an oven thermometer and the instruction on your ovens owners manual (most makes and models are online to Google) With precise measurements of ingredients, time and temperature almost* any one can turn out top class baked goods.
*There's always some people that need extra help/practice. Rare is the truly hopeless individual.