Parents generally set an Internet Access Schedule for an entire day (e.g. 7am-8pm), while limiting Entertainment Time to a few hours over the course of the day (e.g. 2 hr/day or 30 min/AM and 1 hr/PM).
Any unused Entertainment Time automatically rolls over to the Time Bank where kids can "withdraw" on a later day when they've used up their Entertainment Time minutes (e.g. 15 min/weekday, 30 min/weekend day).