Fellow boomers, help me out here: Am I (to use a Bushism) misremembering our youth?

The last couple of days, I've had a couple of enterprising young fellows- 16 year old high school students - from the neighborhood doing some yard work for me. They were very personable and confident (somewhat overly so - but they are 16) young fellows of seemingly at least average intelligence. I would bet they both do reasonably well or better in school. If you remember the pictures of my house, on the right hand side of the front, there are a dozen like shrubs planted in a bed. The task was to rake out the builder's cypress mulch, install some 55, 19-inch, scalloped, concrete border blocks around the perimeter of the beds, then cover the bed with red rubber mulch. It was immediately apparent that the guys had never put down border blocks before. Not a problem. One thing I can still do well from a wheelchair is supervise. So, I showed them how to do, well, everything. That included pulling a string taut between the two surveyor's stakes on the front corners of the property for a reference line, using my 100 foot tape to mark where to put the stakes at the corners of the bed. Running the line around the stakes at the desired height, using a line level, (they had no clue what the bubble was for) etc. That they really had no clue how to go about it on their own was not at all surprising, given their age. One thing, however, really did catch me by surprise. They almost never understood what I was telling them the first time I told them. I would always have to tell it to them in other more rudimentary language, if not actually roll over and physically demonstrate what I meant. Here, so near as I can remember, is a list of the words and phrases I used which were the absolutely perfect words to convey my meaning, but yielded only blank stares and/or totally inappropriate physical responses. "Perpendicular." "Parallel." "Flush with it." "At a right angle to that one." "At a 90 degree angle." "Square it up." "It's canted to the right." "Staggered." Close the gap." "Tamp it down." "Butt it up." I ended up having to explain what each and every one of those things meant. Question to fellow boomers: Is my mind playing tricks on me, or did every sixteen year-old American boy understand all of those concepts back in the late fifties and the 60s when we were sixteen? I could swear that I did and I would bet you did too. If our recollections are accurate, what in the hell happened? The mythology would have it that today's 16 year- olds are far better educated. Let me take a moment to cut the pathological Jay haters off at the pass here. They earned $80.00 and will do my yard work in the spring and summer.