Science laboratories in education were first used sometime in the late 1800s. Since then, their purpose has changed. A very brief discussion of the purposes of this pedagogic tool will help understand the present ambiguous state of science labs and why the debate over their use in online learning creates such different opinions.
History
The first chemistry laboratory at Yale (1847) was strictly for the use of scientists. Students were not allowed into it.
John Stuart Mill and William Whewell, in the middle 19th century set up definitions of science as an inductive pursuit with careful observations. From these facts, scientists cautiously draw conclusions, set forth hypotheses, and test them.
In the 1880s, universities began to allow students into their laboratories for the purposes of advanced scientific study. Soon, student scientific laboratories sprang into being - even in some high schools. We can imagine that these laboratories concentrated on teaching procedures and techniques that would be essential in a continuing scientific career.
Science courses in schools at that time only taught rote memorization of words, laws, and formulas. Students sat in lectures and read textbooks.
We have the technology to put real experiments on the Internet. I know because I've done it 150 times already. Each of the prerecorded real labs has a number of real experiments ready to use. These labs don't use simulations; they don't use Flash; they don't fool students into believing that science is absolutely precise.