GCFLearnFree.org - Addition and Subtraction
This tutorial consists of a series of short, online, self-paced modules on addition and subtraction. The modules include:
- Introduction to Addition
- Addition of Two- and Three-Digit Numbers
- A Video on Addition
- Introduction to Subtraction
- Subtracting Two-and Three-Digit Numbers
- A Video on Subtraction
Users can create an account to track their learning history. When a tutorial is completed, users earn an Achievement of Completion. Users can see see where they left off in a tutorial, how many tutorials they have completed, print off a Self-Paced Transcript, and download or print their Achievement(s) of Completion.
This online mathematics course is specifically designed for early learners of mathematics, particularly adults who enjoy online learning. Teachers can use the website to supplement their instruction perhaps reaching students who did not understand explanations in class. There is ample opportunity for practice, and assessment is included allowing the learner to see the correct answer for problems they missed. It can be a valuable addition to a beginning mathematics class as long as there is support and additional explanation by a teacher or tutor.
This resource is a good supplement to teaching and learning about addition and subtraction. It introduces the use of number lines and gives good examples of equivalents to demonstrate the equals sign. Practice sets contain contextualized problems as well as problems using numerals alone. The videos assume that learners understand the concept of place (ones, tens, hundreds) so they may be confusing if place has not been introduced prior to viewing. The sequence of modules suggests that the additional and subtraction videos are summary resources but they might also be used as an introductory activity to identify gaps in learner’s knowledge of mathematical terminology.