I agree with Behind Liberal Lines. I will only ask whether your son's forced statement will be part of his permanent record. If so, I would consult an attorney with experience in that area.
Otherwise, Dad (or Mom), you are over-reacting.
If this is like my sons school this 'form' is just a 'time-out' sheet that the kids fill out re-stating what they did wrong and then an example of a better choice they could have made. Nothing more than a talking to in written form, kinda like when we used to have to write sentences. Not a big deal.