It's hardly surprising; most countries tend to gloss over wars they lost, and/or stupid things that their government did, and from the British perspective, the American Revolution qualifies as both.
The odd thing for me is how these things are taught in the US from middle school on. It varies from state to state, school district to school district, and over the years. In my case, our ancient history and US history was fairly comprehensive; particularly on the US history side. There's a gap, however, in what was taught about the rest of the world from oh, say, the fall of the Roman Empire in the west up until the Napoleonic Wars. Rough summaries, but no particular details.