Younger children are more likely to not be sufficiently physiologically developed to handle certain arithmetic operations. This has absolutely nothing to do with intelligence. It is simply a normal part of a child's development that you should be aware of. Some 7 or 8 year olds will struggle greatly with certain concepts.
The Algebra section on HelpingWithMath.com is being developed over the next few months. The worksheets below are just the beginning as far as pre-algebra and algebra worksheets are concerned.
You'll find worked examples and other guidance here that will help work through the worksheets below.
The worksheets below provide a gradual introduction that can help students learn how to solve equations that include letters. e.g. x + 4 = 7. They allow space for students to write the algebraic steps required to get the correct answer. The bottom two on this list are aimed at students who struggle with memorizing multiplication facts.
As with most HelpingWithMath.com worksheets, you can select the "Show Answers" option to view or print an answer sheet for each of the algebra worksheets listed above..