In the Victorian era, schools had one team. That's why it is still sometimes called, "The XV" or similar. It was the early twentieth century before an additional team emerged, usually called Colts, and involving pupils of any age below 16.
The late twentieth century saw an explosion of teams, driven, in part, by parental demand for pupils of all abilities to be involved in school matches. The pendulum swung dramatically, as schools found a badge of honour in the number of teams fielded every weekend. The alphabet game was established, with A,B,C and D teams, and schools were excluded from the top tier of competition based on their inability to match the number of teams boasted by the biggest schools.
This profusion was based on compulsion. In the drive for more teams, choice had to be suspended. Everyone played. The challenge for the games programme was only the pupils who didn't neatly divide by 15, 11 or 7. Massively complex logistics ensued. Sometimes children we the beneficiaries of these opportunities: more often it was bus companies.
Does it still work? Undoubtedly in some places it still does, though increasingly rare is the school that fills its teams with enthusiastic participants, especially for long away games. Particularly in the summer term. The badge of dishonour is to make the Friday call cancelling the bottom ability match, so many schools expend efforts forcing, cajoling and threatening to fill up Saturday's teams. Or breathing a sigh of relief if the opposition cancels first.
A number of factors contribute to this decline in enthusiasm. Reluctance of schools to insist on levying compulsion, decline of the honour of selection, alternative leisure activities, parental complicity with unavailability, growth in numbers of overseas pupils: all have contributed in their own way.
So, what does the future hold? Undoubtedly, a significant proportion of pupils will continue to be keen to play team games, and will relish the excitement of competition, plus the camaraderie of playing with friends. And schools will continue to attach cultural significance, celebrate successes and invest heavily in high performance. And might legitimately aspire to provide regular coaching and competition for all pupils who want it. But maybe the attempt to add more and more teams in the principal games may recede. Maybe the future measure of a school's programme will be the number of children who choose to be enthusiastically involved in inter school competition in traditional games - rather than the number who can be compelled to do so. The former number will probably be smaller. Compulsion to play, especially in Rugby, is living on borrowed time.
So what of the others? There is an organisational expedient of including a lot of pupils in Saturday matches, especially in boarding schools. But does it all have to be the same activity? Maybe there will be fewer Rugby/Netball/Hockey/Cricket teams. But possibly more Basketball or Badminton ones. The idea that the same activity will engage all people is not consistent with recreational patterns of wider society, where different styles of activity are preferred by individuals.
The opportunity to compete might be available to all. But tempered by a realisation that this will probably not be met by a single activity per sex - and also by a recognition that science says that some people will be disengaged by competition, and respond positively to different types of physical activity.
If the wider ambition of a school is to stimulate in all pupils a positive attitude to physical activity, it may be that a more complex programme will be needed to achieve this.
