I'm sorry but.. safety procedures (and training), paperwork and thorough tracking of substances are a huge part of actual experimental science. Yes it may be discouraging that a young child can't just go and do the experiment they want unhindered but that's not how safety works. Even mundane non-cleanroom handling isn't allowed until the right safety training is taken (yearly basis).

P.S. Yes I'm aware a number of these chemicals can be picked up locally at Home Depot etc. to be "played" with at will, but this doesn't negate how public-funded experimental research is done.