Tell and write time to the nearest minute and measure time intervals in minutes. Solve word problems involving addition and subtraction of time intervals in minutes, e.g., by representing the problem on a number line diagram.
Official wording from the Common Core State Standards for Mathematics (Β© 2010 National Governors Association Center for Best Practices and Council of Chief State School Officers). View on thecorestandards.org
Third graders read analog and digital clocks to the exact minute and write the time correctly, so a clock with the hour hand just past 4 and the minute hand two marks past the 7 reads 4:37. Reading to the minute depends on counting by fives around the clock face and then counting on single minutes, and on noticing where the hour hand sits between two numbers.
The bigger idea is measuring time intervals. If soccer practice starts at 3:45 and ends at 4:30, how long is it? Students solve these elapsed time problems by jumping along a number line: 15 minutes from 3:45 to 4:00, then 30 minutes to 4:30, making 45 minutes in all. They also work forward and backward, finding an end time from a start time and duration, or a start time from an end time. Because an hour holds 60 minutes rather than 100, regular subtraction of clock times often gives wrong answers, which is exactly why the number line strategy is so valuable.
At 4:50 the hour hand is nearly at 5, so students may read 5:50. Remind them the hour does not change until the minute hand reaches 12.
Subtracting 3:45 from 4:30 as 430 - 345 = 85 gives 85 minutes, which is wrong. Use a number line that jumps to the next whole hour.
Children sometimes count minutes from the hour hand instead of from the 12. Minutes always start at 12.
Swapping the hour and minute hands turns 2:35 into 7:10. Point out that the short hand is the hour hand.
A movie starts at 2:35 and ends at 4:10. How long is the movie in minutes?
Answer: The movie lasts 95 minutes (1 hour and 35 minutes).
Give every student a geared clock so the hour hand moves realistically with the minute hand. Practise skip counting by fives around the clock until it is automatic. Draw elapsed time number lines with landmarks at whole hours and half hours, and have students label each jump.
Assessments usually show a clock and ask for the time, or describe a schedule and ask for a duration, start time or end time. Problems that cross an hour are the ones that separate understanding from guessing.
Original questions written for this standard. Choose an option or type your answer, then press Check. Every question has a worked explanation.
Answer: C) 4:37
Counting by fives to the 7 gives 35 minutes, plus 2 more is 37. The hour hand has not reached 5, so it is 4:37.
Answer: 45 (also accepted: 45 minutes)
3:45 to 4:00 is 15 minutes, and 4:00 to 4:30 is 30 minutes. 15 + 30 = 45 minutes.
Answer: A) 6:55
6:20 plus 35 minutes: 10 minutes to 6:30, then 25 more minutes to 6:55.
Answer: 11:35
Count back 15 minutes to 12:00, then 25 more minutes to 11:35. 15 + 25 = 40 minutes.
Answer: 35 (also accepted: 35 minutes)
8:50 to 9:00 is 10 minutes, then 9:00 to 9:25 is 25 minutes. 10 + 25 = 35 minutes.
Answer: B) 20 minutes
From 2:50 to 3:00 is 10 minutes and from 3:00 to 3:10 is 10 more, so 20 minutes. Clock times do not subtract like ordinary numbers.
Tell and write time from analog and digital clocks to the nearest five minutes, using a.m. and p.m.
Fluently add and subtract within 100 using strategies based on place value, properties of operations, and/or the relationship between addition and subtraction.
A full lesson with slides, activities and an exit ticket on telling time and elapsed time to the minute, pitched to grade 3 and editable in PowerPoint or Google Slides.
Make a lesson βA printable, differentiated worksheet on 3.MD.A.1 with an answer key, ready in about a minute.
Make a worksheet βTurn telling time and elapsed time to the minute into a quiz students answer online that marks itself, with a class summary for you.
Build a test βThe standard focuses on telling time to the minute and measuring intervals in minutes. Many programs mention a.m. and p.m., but the core skill is minute-level time and elapsed time.
An open number line with jumps to friendly times, such as the next hour, is the strategy the standard suggests. It avoids errors from treating clock times as base-ten numbers.