Elapsed time is the amount of time that passes between a start time and end time. Within an hour, students can count up by fives and ones, or subtract minute values, to find elapsed time.
Elapsed time is the gap between a start time and an end time — the answer to "how long did that take?" You already know how to read a clock to the nearest minute, which means you can identify both the start time and the end time precisely. The new skill is calculating the difference between them.
The most reliable strategy within a single hour is counting up: start at the start time, and hop forward in convenient chunks until you reach the end time, keeping a running total of the minutes you have added. Because a clock face is divided into groups of 5 minutes, counting up by fives is natural. For example, if a movie clip starts at 2:14 and ends at 2:47, you can count up from 2:14 — hop to 2:15 (1 minute), then count by fives: 2:20, 2:25, 2:30, 2:35, 2:40, 2:45 (that is 31 minutes so far), then add 2 more ones to reach 2:47. Total: 33 minutes. The counting-up approach mirrors what you do naturally when making change — you count forward from the price to the amount paid rather than subtracting directly.
Once you are comfortable counting up, you can also subtract the minute values directly: 47 − 14 = 33. This arithmetic shortcut gives the same answer and can be faster when the numbers work out cleanly. The key condition for this shortcut is that both times are within the same hour — start and end times have the same hour digit. When you cross from one hour into the next, the subtraction gets more complicated, and the counting-up strategy remains the safest option. For now, staying within one hour keeps the focus on understanding what elapsed time means and building fluency with minute arithmetic before tackling the harder cross-hour problems you will encounter next.