I think you need to take some time and asses why your getting blocked. for example.

1. Am i jumping high enough?
2. Am i protecting the ball both when im driving and going up for a layup?
3. Am i going up with 2 hands?
4. Am i assesing the defense before driving in order to know you can make the shot without getting blocked (know your limitations)
5. Can i go with either left or right hand strong?

those are just a few of the possibilitys that could be stuffing your layups up, on the other hand your only very young so i wouldent worry bout it to much, if you want id start practising floaters or runners in the lane before you even get near to getting blocked like tony parker or steve nash does.

Curtis~

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