The reason why the concept of time is not a major part of the course is because it was supposed to concentrate on the physical aspects of Earth. I read your "trip through time" and found it a perfect example of how an everyday experience can be used to convey the concept of dark time. In order to accomplish that feat, one must use a common experience. One that I have used when I taught historical geology employed a roll of Scott toilet paper. Actually, the idea didn't originate with me; I sort of stole the idea. The Scott people claim a roll of their toilet paper it consists of 1000 sheets. I must admit that I took their word for it, not wanting to spend my time to check to see if it does indeed contain the specified number of sheets. In any case, with 1000 sheets, every sheet represents 4.5 million years. Then the fun begins,. One sheet represents the entire time of human existence on the planet. Homo sapiens showed up about a half sheet ago with the written word going back 1/10 of a sheet. I suppose one could contemplate all that when one while taking part in ones daily constitutional.