Well, let's focus on pre-assessment. If we take a look at the diagram above, we know that pre-assessment activates students' prior knowledge to expose misconceptions and reveal knowledge gaps. So...again...why do it? Well, the simple, one worded answer is: differentiation. If the learning experience/s can be tailored to the individual's needs, then we have a more successful model of learning since the individual is presented with specific opportunities, enabling them to acquire new knowledge and skills by way of various systems and/or environments.
Let's say I wanted to teach to this content descriptor for Year 5: "Identify and describe multiples of whole numbers and use them to solve problems (Australian Curriculum)." I would then use a basic pre-assessment (such as the one below) to gauge their understanding and fluency of multiples first. The data would then be analysed and for those who struggled with the pre-assessment, an emphasis on understanding and fluency would be a priority. For those students who passed the pre-assessment, the activities would be designed to focus on problem solving and reasoning. Since these skills are classed as higher-order thinking, your gifted and talented students will be catered for (especially if the activities are open-ended)!