Look at this weight bar:

http://bigfitness.biz/search-images/i/olympiccurlbar.jpg

you see the hollow cylinders at the end..Well you can make them bigger and slide in a cylindrical rock that weighs the amount of weight you want and you just close the lid...you can even drop a cylinder of plastic with sand, or liquid, or soil or dust [like a plastic bottle]...And the cylinders of the weight bar you can make them as wide as you like and as thick as you like...

you can even make dumbells out of them...

Some Thoughts:

How to make your kid the most WELL BEHAVED KID IN THE HISTORY OF THE SCHOOL even though it will be cruel and it might be too much...lol...

You have him/her put an x strap in his chest one he/she cant get off only you the parent...this straps sends sends a tiny, very tiny, will not hurt a kid, a tiny pulse of electricity so tiny it will not harm a kid or a needle pistol that taps the skin...Both at your cell phone signal command...you place computer cameras all over the house all hooked to your cell phone..every now and then you turn on your cell phone to see what he/she is doing..You see him/her doing something you disapprove you send the signal and he gets a small electrical charge very tiny or a needle tap..

Tell me after 1 month if he/she will not behave good...It is cruel though...

Some Thoughts:

You know how about a hybrid type of baseball...Instead of the diamond shape of the bases there is an: X shape..and every vector of that X when the hitter hits the ball at the end of each vector the player must run going around the X....In fact you can make the shape be many letters of the alphabet or 2 or 3 letters joined together...