I am wondering what you think about this - sub quickly and often, or let players on field play longer stretches (which means the subs sit for longer stretches). As a simple example to illustrate, let's say you are playing 5v5, 20 min halves. You have 10 players (so 5 subs). On one extreme end of the spectrum, you could let the 5 starters play the entire first half (20 mins). And simply play the other 5 the entire 2nd half. Swap 5 for 5. On the other end of the spectrum (high frequency subbing) you could sub out all players every 5 mins. In both cases every player has played the exact same num of minutes. Which is better at U8? I think the age matters. At older ages you don't see frequent subbing. But at ages 5/6/7/8... does it make more sense to sub players in and out frequently? If they sit on the bench too long will they get disinterested, get sad, clown around too much on the sideline, etc? Sub frequently to keep them more engaged?
Leaving them on the bench for a half would be beyond stupid. Ar U8 our league is 4v4 with 12 minute quarters and a roster size of 8. For simplicily lets assume all 8 are there. I sub everyone 1/2 through each quarter. For my older teams that play halves. I still sub 1/4., 1/2 and 3/4 through the quarter unless I see that someone is really struggling. To be clear though-- I'm a rec coach and everyone is playing 1/2 of the game.