## Description

This math app can be used to teach and study the partial differences subtraction method. The app is easy to use and it has an intuitive interactive interface with customizable colors and other settings. The user can solve random subtraction problems. The number of digits in the numbers can be set.

Endorsed By Teachers

R. Zeni, Ecole Sandy Hill Elementary, Abbotsford, BC, Canada:

"The math apps by Esa Helttula allow students to practice and reinforce the specific computation strategies taught in class, with as much or as little scaffolding as necessary. They also provide individualized feedback to each student, with an immediacy that is not always possible through pencil and paper practice. Being able to adjust the level of difficulty to suit their needs is also very motivating for the students. I am so glad to have come across this great educational tool!"

More endorsements from teachers can be seen at my site: idevbooks.com.

The Partial Differences Subtraction Method

The partial differences subtraction method is a two-step process. In the example 936 - 580, each place value is first subtracted separately from left to right. The partial differences are added and 400 - 50 + 6 produces the answer 356.

In the Everyday Mathematics curriculum the partial differences method is one of the algorithms for subtraction.

The App Is Easy To Use

The numbers are aligned automatically so that the user can concentrate on solving the operations for each column.

After you solve the operation for each column the correct answer will fly to the right place. If you press the wrong button the answer will appear above the keyboard but it will not move.

Settings:

- Each number can have from 2 to 3 digits
- Problems can be custom or random
- The current operation for each column can be hidden
- The operands of the current operation can be highlighted
- Colors of the interface can be changed
- The speed of the animations can be set
- Open worksheets of up to 10 problems that are made on the iDevBooks.com site

Other iDevBooks math apps

iDevBooks math apps have been reviewed and endorsed by Wired.com, IEAR.org, Edudemic.com, Teachers with Apps, and other respected sites and organizations.

Some of the other 24 iDevBooks math apps are Column Addition, Long Multiplication, Long Division, Column Subtraction, Visual Multiplication Table, Partial Quotients Division, Partial Products Multiplication, Partial Sums Addition, Decimal Rounding, etc.

Feedback and requests for new features

New ideas to make this app better are welcome. Please visit idevbooks.com to give feedback.

Privacy

This app has no ads or in-app purchases and it does not transmit any data during the operation of the app. This app also does not contain any links to other apps or the web.

## What’s New

Version 5.2

- support for iOS 12
- support for iPhone Xr and Xs Max
- minor bug fixes

5.0 out of 5
1 Rating

## Information

Seller
Esa Helttula
Size
3.3 MB
Category
Education
Compatibility

Requires iOS 8.0 or later. Compatible with iPhone, iPad, and iPod touch.

Languages

English

Age Rating
Rated 4+