" I hear what you say, but it seems to me more likely that a near-15 year old is more likely to be in tune with 11-13 year olds than you are.
The point is that with a Pi, things ARE "doable". with this BBC device they appear not to be - or if they are, they're not significant enough to maintain the kids attention"
I have both a 14 year old (15 in June) and a 13 year old.
And got a completely different response from them both compared yours.
So being "in tune" as absolutely irrelevant. Unless you believe all children are absolutely identical.
With a Pi, things are doable at school Except.
They have to have wires coming out of all four sides, they have to find a HDMI monitor (most schools still rely on VGA stock) or a HDMI to VGA adaptor.
Then when they are up and running what can they do? Hello World?
With this thing, the 13 year old plugs it into a USB port and goes to a web page and the LEDs flash.
Will it hold their attention? No, we hope not. It's just the spark, then they move on to the Raspberry Pi. Or more likely they run Python Idle on the computer they were using with the Micro Bit because they still can't plug the Pi into a VGA monitor.