Dividing with Remainders
Students used tiles to help them divide. I wrote a division fact on the board and students drew groups and used the tiles to divide. We talked about how division is about splitting an amount into smaller equal groups. We also talked about how sometimes there are left overs that we cannot divide evenly into the groups; these are called remainders.
Then students learned how to use multiplication facts to solve for division problems.
Students used skip counting to find multiplication facts.
EX: 28 / 5 = ?
First, students determined if 28 would divide evenly into 5 groups. One way we can tell if a dividend divides evenly by the divisor is if the dividend is a multiple of the divisor. I can tell 28 is not going to be divided evenly by 5 because 28 is not a multiple of 5. Students skip counted by 5s in order to find a multiple/product that was close to 28, but does not go over.
5, 10, 15, 20, 25 --- I stop at 25 because if you continue 30 is greater than 25.
We know that 5 x 5 = 25 so 28 / 5 = 5 with a remainder.
We know the difference between 25 and 28 is 3, so my remainder is 3.
Sorry, for some reason it's not letting me embed the video to this post.
Another method students learned was the Box Method. Some students may find this way to be easier. As always I tell students to use whichever method they are most comfortable with. They always have options.
Monday, October 7, 2013 Students learned how to use rounding to estimate products. A few things students must remember: -You must round first before you do any calculations. -You must round the number that is not the single digit number. -You must round to the greatest place value.
EX: 7 x 234 = ---> 234 rounded to the nearest hundred is 200 so we re-write the problem as 7 x 200 = ---> then we multiply 7 times 2 which is 14 then add 2 zeros. The estimated product is 1,400.
Here is a helpful video (full screen to make bigger):
Reminders: Tomorrow, Thursday October 10th, is Curriculum Night for K-5. There will be different sessions if you plan on attending, here is an overview and schedule of the sessions:
Room 148: Third, Fourth, Fifth Grade Mathematics Curriculum. Presented by Ms. Kominczak, Mrs. Cao, and Mrs. Gayer. Discussion of math curriculum and STAAR Math testing. View EnVision/Pearson website and receive log-in information. Discussion of ways parents can help students at home (STAAR practice, etc.). Session Times: 5:10 pm; 5:30 pm; 5:50 pm; 6:10 pm
Students learned that there are special rules for dividing numbers by 1 and by 0.
Rule: A number divided by 1 is that number.
Examples: 4 / 1 = 4 or 55 / 1 = 55
Rule: A number divided by itself (except 0) is 1.
Examples: 17 / 17 = 1 or 135 / 135 = 1
Rule: Zero divided by a number (except 0) is 0.
Examples: 0 / 4 = 0 or 0 / 15 = 0
Rule: You cannot divide a number by zero. Examples: 7 / 0 cannot be done. 12 / 0 cannot be done.
Students didn't get to watch Division Rules video because my projector lamp went out :(
Tuesday, October 1, 2013
Students learned to use patterns to multiply by multiples of 10s and hundreds.
An example we talked about in class was:
EX: 6x800 --- First multiply the first non zero digit, 6 times 8 which equals 48 then add 2 zeros, so your product is 4800.
Wednesday, October 2, 2013
Students learned CUBES for solving word problems. I sent a copy of CUBES home for students to keep and use for future assignments.
[Edit] Reminders: -All grades are updated in the grade book/database; this includes test that students took on Friday 10/4/13. -The end of the first 9 weeks is October 18, 2013. All make up or late work is due Tuesday, October 15, 2013. I will not take any missing work after Tuesday 10/15/13. -Within the next week, week and a half, we will be taking Math Benchmark 1. I have scheduled Benchmark 1 for Wednesday 10/16/13. I will keep you all updated if there are any changes.