Information: Boy in military or civilian uniform?

[Bobbie Carnegie]

This among an interesting bunch of late 1800s and early 1900s glass plate negatives that Harrow School has offloaded from their archive are now up for sale on Ebay. Is this lad in military uniform, or is he in some civilian gear that, for example, hotels dressed their minions up in? Maybe he's a 'Telegram Boy'. Anyone recognise his get-up?

Thank you

[Dr. Joe Rock]

I don't think Boys Brigade. The cap badge looks like a Tudor rose with two stakes? I wonder did the school have a boys regiment?

[Wilson Laidlaw]

I think he may be a member of the Boys Brigade. 

Wilson