My son who is 12 year old study in class 7. he is very careless . He is very less power to cram the things.
Even I cram the things when I teach him. How can I imporve his capabilities.

I am not sure what you are asking. Is he failing in school? Being lazy at it? Could you give more details?

Perhaps it has nothing to do with laziness on his part at all. Have you ever had him checked out by the school system. Call and ask them if he can be tested.

Maybe he is a kid that cannot retain everything at once, like cramming it down his throat. Perhaps instead of cramming, why not sit down every night and have him go over his assignments, maybe re-read what they did in class.

If you speak with his teachers, and they also see a problem and agree to him being tested, and it just comes down to were he may have a retention problem, see if they can just advise you what is necessary for him to study for the test. So instead of him studying an whole chapter, they can limit it down to what they will test over, since those items apparently are what they want the students to retain the most. You will be amazed how much this help those students, it gives more structure.

So I guess my thoughts are don't get frustrated get results YOURSELF, cramming may NOT be your child's ANSWER!!

First by doing regular study and never "cram" for study or tests. If a child ( or anyone) has not learned the material in class and by regular study, a cram is not going to make any long term goals.