Every student pilot needs a ground school of some sort. Aviation, after all, is both a theoretical and practical skill. The practical side of aviation is represented by the flight lessons you have with your instructor, where he sits in the copilot’s seat and teaches you how to fly the aircraft.
On the other hand, the ground school presents a forum where you can interact and share ideas with your instructor and fellow aviators. Now, Part 141 flying typically comes with a ground school: it’s part of the package. For Part 61, (more private aviation flight training you’d have to find your own ground school. This would come with an added expense. Now, since you are spending money on it, you should then find ways that you can get the most out of your ground school.
Before I go on if you're confused as to the differences between Part 61 and Part 141 you should read this.
First of all, you need to pay attention. This goes if you're doing a traditional classroom style ground school or even attending an online ground school With this, you should be able to understand most, if not all, of what’s being talked about. Even a second of inattention can cost you a lot, especially if you are not able to ask questions or ask the instructor to talk more about the topic.
The instructor is not perfect. He has the necessary knowledge, but he may not be able to give you everything there is about the topic. Remember teaching styles differ, you have to ask questions if you want to understand more. Most student pilots make the mistake of being too impatient or too eager to get up in the air that they fail to ask questions while on the ground. Thus, they don’t achieve the right understanding of the topic because they did not bother to find out more from their instructor.
Remember this: It's much easier to teach a concept on the ground then go apply what you know to the air. It also saves you a ton of money.
Self-studying is perhaps the best way to take advantage of your ground school. The ground school is there to teach you about theories but, with a time constraint, there is no guarantee that it can give you everything you need. You need to make up for these by self-studying, to make sure that you get the most amount of knowledge from your ground school.
If there is something you don’t understand and your instructor is not able to enlighten you about it, then consider getting additional information from other instructors or other aviation blogs like this one!