Working memory capacity increases with age and in general, a person can hold 5-9 items in their working memory at one time. Working memory is limited by content and time. Only a set number of items can be considered in the working memory at one time, therefore chunking material is essential. When items are chunked together, they are viewed as 1 piece of information.
One can only hold information in our working memories for 2-3 seconds, if it isn’t encoded into long term memory it is lost until it is heard again.
Cognitive load theory relates to the amount of information that working memory can hold at any one time. We should aim to increase the intrinsic cognition (which is the characteristics of the material itself) and reduce the extraneous load (unnecessary and distracting information).
In reducing cognitive load we can reduce the demand on learners’ working memory and help them learn more effectively.
Here are some strategies to help.
Scaffolding tasks can really help reduce cognitive load Scaffolds
Additionally here is some guidance in achieving ‘low sensory’ classrooms.