the most important thing with children is dietary habits. what a great time to present them with good food - mostly(and sort of in order of priority) raw, organic(free of chems and genetic hanky-panky), local, nutrient dense and fermented food.
i have not researched for selenium and boron, but those would be very helpful. ginagirl may have a better idea as i believe she has been using them with children.
as for iodine, its as essential as the air they breath. i really like the CDCs schedule of dosing for nuke emergencies for two reasons - one is they say it and two i know wolf-chaikoff is wrong. i would say this is the minimum dose for children and that would be sufficient. this schedule would allow you to give extra in the event it was needed, like for food poisoning and upper respiratory infections and such. adults can take a gram a day indefinitely. that is seven times the 150mg dose. so you can rule of thumb it and suppose a child could handle up to seven times what they are used to. i am not suggesting a dose with this formula, just letting you know how much room there is before you risk giving too much. i dont see how you, in good conscience and paying casual attention, could ever give them too much at these levels. one day and its all out if there are any concerns at all. if you find that this dose creates an ongoing runny nose and such, something in the environment is causing it - a continued and extreme exposure to a halogen or like chemical. dehydration can cause this as well. noah gets his sippy cup filled with water dosed with a little emergen-c. he calls it juice, but its just mineralized water. distilled water at that. hydration is more important than even iodine.
Adults should take 130 mg (one 130 mg tablet OR two 65 mg tablets OR two mL of solution).
Women who are breastfeeding should take the adult dose of 130 mg.
Children between 3 and 18 years of age should take 65 mg (one 65 mg tablet OR 1 mL of solution). Children who are adult size (greater than or equal to 150 pounds) should take the full adult dose, regardless of their age.
Infants and children between 1 month and 3 years of age should take 32 mg (Ĺ of a 65 mg tablet OR Ĺ mL of solution). This dose is for both nursing and non-nursing infants and children.
Newborns from birth to 1 month of age should be given 16 mg (ľ of a 65 mg tablet or ľ mL of solution). This dose is for both nursing and non-nursing newborn infants.
so that is two drops of SSKI per child. i would go to three drops at the onset of puberty regardless of weight and maybe a little sooner if they are good sized kids. five drops is the minimum i recommend for adults per day. if circumstances dictate - if you have a new car that they ride in a lot, exposed to other environments where bromine is very prevalent like a school that is carpeted, eat a lot of junk with their friends, have been exposed to fluoride(fluoridated water in the school drinking fountain), oh heck, the exposure is numerous and insane, then you can give more. you will have to pay attention and judge for yourself. the main thing is a daily dose. dont skip. if you have to watch them down it in some juice every morning, dont skip.
i found that putting Iodine in milk was very helpful. if they drink milk every day(you know if it isnt raw or if its used to eat cold cereal, as convenient as that is, both are a nightmare!) that actually does give them the opportunity to increase their own dosage through body cravings. once the body learns, it can be smarter than cerebral thought. i just throw that out there in case it resonates with you.