Twenty minutes before the end of Andrew M's year 11 rugby match there was a bad tackle between two of the children.
"Suddenly, the tackled boy's burly dad strode onto the pitch to tell the other kid off", says Andrew, "the tackler's equally burly father didn't like that one bit, and charged after him." A fight started. Teachers got involved, and before they knew it, a full-on brawl erupted. "The match got called off," says Andrew, chuckling at the memory.
When it comes to sidelines etiquette, that has to be the biggest no-no in the book. It's wrong on so many levels it's impossible to list them all.
But badly behaved parents on the sidelines come in all shapes and sizes - and they're more common than you might imagine. It's not surprising that many children feel intimidated by parents who seem to mistakenly believe they're watching a World Cup final.
[Related feature: How to be a supportive parent without being pushy]
Andrew now has a child of his own. His daughter, Donna says that parents who scream and shout on the sideline are "embarrassing for their kids and pretty scary for the rest of us". Andrew assures us he restricts himself to polite applause and the odd cheer.
So what are the rules for good sidelines etiquette? Here's our handy guide for parents who might be confused.
1. You are not the coach
We know that deep down you believe that you'd have been the best gosh darned under-10s coach Welshpool Junior school has ever seen, but this isn't your chance to shine -- it's your chance to stay quiet and let the real under 10s coach bark orders. For some crazy reason, the kids find it confusing when more than one person is shouting at them. Patience, my friend, your time will come.
2. Don't diss your team
So you think young Cedric is the worst fly half this universe has ever seen? Probably best if you keep that to yourself -- that's his mother standing next to you.
3. Don't diss their team
Until the players on the team are earning a seven-figure salary and training for eight hours a day, your comments about the poor standard of play may come across as a little distasteful.
4. The referee knows best
Unless your school has access to the third umpire complete with hawkeye and a slo-mo replay, it might be best to let the ref do to the reffing. Weirdly, grown adults who pound onto the field mid-way through a match look kind of foolish. It's a mystery, but there it is.
"One of the things I hate," says Chris G, junior cricket umpire and volunteer coach, "are parents who patronise you by saying you made a good decision. Firstly, I don't need your approval, and secondly, you're only saying that because the call went in your team's favour. Those are the parents who come up to you afterwards to give you a review of your performance and tell you all the times you were wrong."
5. Do keep still
So you get really pumped when your team plays well? You like to follow every second of play and be right next to the ball wherever it is? You want to cheer right into your child's ear? Well, you're really annoying the kids, the other parents and everyone else nearby. As Jeremy W, aged 15, puts it: "the parents who do that just look stupid. I mean, what are they doing?!"
So there you have it, follow these simple rules and you too can pass for a normal, level-headed, sports-loving parent who thinks everyone played marvelously and who just enjoyed coming out to show support. No one will ever know that you're freezing and grumpy and that you could have done a much better job if you'd been playing, coaching and refereeing the whole thing.
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