Stacking, streaming and adapting are three different things

Four terms

Keep them apart and both the parents’ meeting and the board meeting get shorter.

• Selection: picking those who are best at the moment, or judged likely to become best, for matches, camps, teams or training groups.
• Streaming: dividing by skill level. Permanent streaming is in practice the same thing as selection.
• Adapting: dividing by ability within individual drills or phases, and doing it flexibly. This is the variant that is recommended.
• Stacking: a form of selection where those who are best at the moment get an advantage in competition — a guaranteed place, more playing time, or better opposition.

What the rules actually say

In Swedish sport, children’s sport runs to age 12 and youth sport begins at 13. That is a sharp line, not a gradual shift: only from 13 are league tables kept and overall winners declared. The Swedish Sports Confederation’s guidelines nevertheless apply all the way up to and including 19, and rest on five principles — safety, participation, joy, versatility and health.

Two things are often misunderstood. The first is that the age of 13 is a starting gun for splitting into recreational and elite. The guidelines say the opposite: cohesion matters especially in early adolescence. The second is that a focus on results is banned. It is not — the result may matter in the moment, but it must not have long-term consequences for who gets to play and develop.

At the same time the Confederation is clear about what research shows: permanent streaming and early selection reduce both a sense of belonging and perceived competence — and that holds regardless of which group the player ends up in. That is worth noting, because the argument for streaming is nearly always about developing the top group.

The tape measure is your most important tool

Measure the height of the whole squad three or four times a year and record how much each player has grown since last time. It takes twenty minutes a time and gives you the single biggest hidden variable in the 13 to 15 age range.

The difference in biological maturity between two players born the same year can be several years. Academy players grow on the order of eight to ten centimetres in the year around their growth spurt, and it arrives at very different chronological ages. What you see on the pitch during that year is partly maturation and only partly football.

The practical reason to measure, though, is not selection but injury risk. It peaks in the six months after the growth spurt — exactly the period when many clubs increase training load and start selecting. If you can see the spurt coming you can reduce load in time, take knee and heel pain seriously immediately, and expect temporarily worse coordination without reading it as a lack of effort.

Count the birth months in your squad

Write down every player’s birth month and compare January to March with October to December. If the first quarter dominates, you have most likely selected on age without realising it.

The effect is well documented in Swedish football: players picked for district and youth national teams are heavily skewed towards being born early in the year. And it does not arise on its own — it is created by coaches’ selections. A whole-population study shows the effect is largest in the youngest ages and almost gone in the oldest youth ages, which says something uncomfortable: many of those we deselected early would have caught up.

One concrete counter-measure is bio-banding: for a few sessions each term, build the teams by size and maturity rather than by birth year. Later-maturing players then get room to show technique and decision-making without being physically overrun, and earlier-maturing players are forced to solve situations with something other than their body. Run it as a recurring feature, not as a once-a-year project.

Write the playing-time policy before the season

Playing time is one of the strongest predictors of whether young people continue or quit, and what children mean by "fun" largely comes down to being in the game. So playing time is a policy question, not a decision to be made in the heat of the moment on a cold Saturday morning.

Decide it before the season, write it down, and tell both players and parents. One arrangement that works for ages 13 to 16 is that everyone plays at least half the match, that deviations may only be based on attendance and conduct, and that whoever sat out most in one match starts the next. Then you follow up — a policy nobody measures is a statement of intent.

Use the balancing tools already in the rules instead of playing out a lopsided match. The four-goal rule is the clearest example: four goals down, you add a player; four goals up, you take one off. A match standing 9–0 at half time develops neither team.

Define the win before the match

If the result may matter in the moment but must not drive development, you need something else to evaluate against. So decide before kick-off what you want to see, and assess afterwards against that definition: playing out of the press along the ground, the back line staying compact when the ball comes in, repeating the run in the second half.

Give every player an individual development plan in three parts — football, wellbeing and life outside — and hold a short conversation at least once a term. That is the model Swedish football uses in its upper secondary programmes, and the most common shortcut is to keep only the first part.

And ask the players. In the Confederation’s own survey, close to 40 per cent of leaders said there was no way — or at least none they could think of — for the children to influence the activity. Something concrete each month is enough: a drill, a warm-up routine, a team rule, the plan for the tournament. At the same time, be open about what they do not get to decide.

Common follow-up questions

Is streaming always wrong?

No — but the flexible variant is the recommended one. Divide according to what an individual drill demands, redo the grouping often, and avoid permanent tiered teams in the early teens. The difference from selection is that a player can end up in a different group next week without anything dramatic having happened.

We have 22 players in the squad. How can everyone play the same amount?

Not necessarily within a single match — but they should over a season, and that is where you should measure. Rotate who starts, record playing time match by match, and let the number drive the next selection rather than your gut. If the squad is too large for the format, that is a registration decision, not a playing-time problem.

What do I do with a player who is clearly better than the rest?

Give harder tasks, not a different team. More touches under pressure, worse starting positions, fewer touches allowed, a position that demands more. Moving a player up permanently solves one season and often costs them their sense of belonging, and the research is notably sceptical about how well we judge who is actually best at that age.

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