When I was in grade school they tried to prepare us for the metric system. They did this by making us convert back and forth... by hand... on paper. The end result of this was to convince us that the metric system was very complicated and a lot of work. Of course this is not true. When I took chemistry and physics, of course, we did everything in metric and it was simple. We just measured it with metric instruments... When the law was about to go into effect that we HAD to go on the metric system, I was working as a carpenter. The old carpenter I worked with was saying how much work it was going to be to convert all of the measurements back and forth. I tried to explain to him, you just buy a metric ruler and measure everything in metric and the blueprints, once we all go to metric, will all be done in metric. There is no converting back and forth. As it is just doing imperial without converting to metric, I'm constantly converting fractional inches into decimal inches to do math and then changing back after the math. Or feet into fractional feet and then converting to inches... It is a real pain. It's also the reason a REAL rafter square has one side with tenths of an inch on it...
They TAUGHT us to hate the metric system by how they tried to teach it.