This activity develops students’ understanding of hours and minutes as units of time, and helps them to see 1 hour as 60 times as long as 1 minute.

In converting hours to minutes, students may reason additively when the time in hours is a low single-digit number, but likely will reason multiplicatively when converting, say, 8 or 10 hours into minutes. When they relate the operation of multiplication by 60 to converting hours to minutes, students make use of structure (MP7). To convert fractional numbers of hours (, and hour), students might choose to think in multiplicative terms (for instance, ) but are not expected to do so. Instead they can rely on their prior knowledge of “quarter of an hour” and “half an hour” to reason about the number of minutes.

• Invite selected students to share their responses and their reasoning. Start with students who reason additively about the number of minutes in a given number of hours. End with those who frame the relationship between a whole number of hours and the number of minutes in multiplicative terms. 

In this activity, students reason about the number of seconds given time in minutes. Students see that 1 minute is 60 times as long as 1 second.

• Display the table. Invite students to help complete the table by sharing their responses and their reasoning. 
• “¿Cómo encontraron el número de segundos que hay en 30 minutos?” // “How did you find the number of seconds in 30 minutes?” (Multiply the number of seconds in 10 minutes by 3, multiply the number of seconds in 5 minutes by 6.)
• Select other students to share their reasoning for the problem about commercial breaks. 
• Highlight that we can decompose the number of minutes to find the number of seconds. (For example, minutes is 1 minute and minute or 1 minute and 30 seconds, which is 90 seconds.)