Silkscreeningsupplies.com offers great starter kits for around 200 dollars. There is also a machine called the yodu (sp) that is an all in one machine, never used it though. If your involving kids, depending on their age, I'd print screen print with water based inks, only because water based inks are easier to clean up and manage. You could also look into heat pressing with ordering transfers and then puting them on shirts with a press, it's clean and simple, only thing is you have a 350 degree press sitting out with small kids around, may not be a good idea