Graphstation
Graphstation is an application which can be used to create graphs and run algorithms.
There are many built in templates to support first time users.

 

Little man computer from KS3 to KS5
Little Robot Computer is a simplified version of the Little Man Computer.
It can be used to introduce the functions of the CPU and demo the Fetch Execute Cycle.

lesson_resources_1.4.3,        CPU Simulator