Over Under - 4

Grade 4 mathematics Routine

over or under

Standards for Mathematical Practice: #2, #3, and #6

In this routine, students mentally compute and use estimation skills to determine if the sum, difference, product or quotient is over OR under a specified amount. 

DIRECTIONS:

1. Students will come to the front of the room with no supplies.
2. Share an amount with the students, ex "Over OR Under 100".  
3. Provide expressions one at a time for the students to consider. 
4. Solicit from the students whether they think the solution is over or under the original amount.
5. Invite students to defend their reasoning while recording different strategies on the board.
6. Facilitate a group discussion.  Consider asking the following questions.

• • What strategy did you use to find your estimate?
  • How was your strategy efficient for you?
  • How did your estimate compare to others?
  • How precise were the estimates?

VIDEO: 

Notice how the teacher reviews various hand signals for the students to show what they are thinking before the routine begins. She sets the benchmark and then gives the students think time to decide if the product will be greater or less than the benchmark. Once most of the class is showing the hand signal for over, the teacher has the students turn and talk in pairs about what their reasoning is. Notice how the students are explaining to one another how they used multiplying multiples of 10 to help with their estimations. The teacher counts down from 5 to wrap up their conversations and turn back to the front. She had a few students share different strategies for how they used estimation to help them determine the product would be over the benchmark. Notice how a student explained how to use decomposing a factor to help her figure out her estimate. After all the ideas were shared, the teacher facilitated a discussion on what other numbers you could multiply by 7 that would be greater than 490 and then a discussion of what you could multiply that would make a product less than 490. The students shared ideas about numbers they could multiply and their reasoning. 

GOOGLE SLIDES: Over/Under Links to an external site.

These slides include directions and questions to facilitate a discussion during the routine. There are 23 sets of expressions with set benchmarks that increase in difficulty as the deck progresses.