Brad,
As power and explosive power is a combination of strength and speed, your athletes must be " strong first ". This is only for 17/18.
Prepubescent athletes should not engage in a strenght training with loads.
The progression to explosive power is :
- muscular endurance
- strenght
- maximal
- speed
- agility
All these sports specifics components must be developed before any kind of power training, for safety considerations, as numerous biomechanics factors and neural activation are insolves.
Methods of long- term power training include :
- heavy resistance training
- explosive light weight training
- maximal power training or ballistic training.
For sports specifics, the ballistic is the best today ( studies by Berger and Wilson et al), and the load is typically around 30 % 1 RM.
Plyometrics exercises are also used to enhance explosive power, but requirements
for this high impact and high intensity training must be strictly followed.
This is " the theory ", and the " good one ! ", now, not easy to write a periodize training program because every athletes has specificities.
You can find the guidelines for all the training listed above on " ACSM " guidelines.
I honestly don't know what is possible to do in matter of power for 12/13, I am not qualified for this age.
I think you were looking for a " magic formula ", quick and easy, impossible if you want to train safe and for long term.
- power
- explosive power.
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