Is coaching in class 12 necessary to score 100 in chemistry?

Coaching is NOT necessary. But one must be ready to develop some qualities/habits to substitute the advantages coaching institutes provides.

1. CONSISTENCY: You must be regular with your studies. Because there will be no external force(of coaching) which will force you to complete your syllabus and practice enough. You will need motivation for this. At times, you may feel bored but try methods in your own way to cope with this.

2. CONFIDENCE: Confidence, that you can do it without taking coaching.

3. PATIENCE: You will need this a lot. You will feel many times that this is not working! You will always have in mind that I am not doing that much better the others are doing. But have patience and maintain consistency, it will pay better at the end.

4. Coping up with PEER PRESSURE: You will see others going to coaching institutes and many times knowing things in advance. This may hamper/destroy the above three required mentioned. To cope up with peer pressure you must have faith in you and that will be generated only if you will feel that you are doing hard work. For that you really have to do hard work.

5. CHALLENGE & HEALTHY COMPETITION: Coaching environment creates a healthy competitive  environment. To substitue this you have to challenge yourself regularly and have a 'silent healthy competition' with others. Also, don't burn out i.e. study 12 hours for 1st month and nothing in next 2 months. Do it at per your ease but consistently.

6. GUIDANCE: 1st thing you can do is to use internet for this. Second thing you can do is to engage your school teacher to guide you, but you must know the art how to do it. OR find some elder in related field who can guide you. OR your discussions with friends who are taking coaching can make you aware about a lot.

It is not easy but doable. Also, you will save money. BUT THE MOST IMPORTANT THING in this way you will develop habits that will continue to pay off till the end of your life. Also, you will not be the student in IITs/NITs/Medical College/elsewhere who will face problems after securing admissions there but not able to withstand with expectations there.