It's a tough one to answer, but it sounds as if your lads are not particularly aggressive, and are unlikely to get away with "giving it back" as other posts have suggested. This is pretty much what I was like as a kid, and I got bullied by an older kid around the local estate from time to time from when I was about 9 until I was 11 or 12 (when I grew). I never fought back, because I saw what he did to kids who fought back, but I slowly learned to talk my way out of it at least half the time, and standing up to the bully by not running away or fighting back or showing I was scared seemed to work.... and if I'm honest, it's done me good in later life, as I still never give in to workplace bullies, can talk my way out of most situations or know how to avoid most of the awkward ones, have self-respect that is not linked in any way to what other people think, and can look after myself without resorting to being violent. So, as long as this doesn't get out of hand (in other words stays at small-time stuff like you describe), tell your lads to stand-up to it, take it as it comes, find out how to avoid it if they can, and just don't let the bully get their kicks from bullying them.