When to foul up 3
The math: two made free throws can't beat you, a made three ties you. Under ~12 seconds, foul on the floor before any shooting motion — target their worst shooter, hands visible, nowhere near the arc. Between about 13 and 21 seconds it's too early: a foul hands them a 2-for-1. Guard the arc, switch everything, and foul once it drops under ~8.
The one exception worth respecting: if they own the offensive glass, the missed-second-free-throw putback is a real path to disaster — put two bodies on the lane before you commit to the foul.
The foul game, down 4–7
Most coaches start fouling too late. A workable rule: start at roughly 15 + 10 × deficit seconds — down 4 by ~0:55, down 5 by ~1:05, down 7 by ~1:25. Get your foul-givers on the floor a possession early, hunt their worst free-throw shooter, and script the offense to score inside 8 seconds every trip. Hold your timeouts for drawing plays; in high school a timeout doesn't advance the ball anyway.
2-for-1 with a 35-second shot clock
With the shot clock at 35, the window is the 41–52 second band: get a good look up by ~41 and the ball comes back to you with 6+ seconds for the last shot — and an offensive rebound on the first trip still preserves the whole thing. Below 38, you're in one-possession territory: initiate your action around 12 seconds, shot by 5, crash two.
Fouls to give
Tied or ahead in the final 20 seconds with fewer than 5 team fouls? You have a free bullet. Spend one around 8–10 seconds into their possession — early in the dribble, never on a shooter — and make them rebuild their set with the clock bleeding.