Source 1 : Desirable Difficulties - How Learning Works What are Desirable Difficulties? DD are challenges encountered during learning that may initially seem to hinder progress but ultimately enhance long-term retention and recall. The core idea of sufficient DD is to increase mistakes during training while minimizing them during actual performance. Three common types of desirable difficulties are: Spacing Spacing involves spreading out study or practice sessions over time Example : Instead of studying for 3 hours straight, break it down into 1 hour sessions each day or across different days. This may result in some forgetfulness, causing students to forget certain things; however, the benefit is that they tend to retain information for longer periods. Interleaving , Interleaving mixes various types of problems or subjects during practice, compelling learners to actively differentiate between them. The diagram below illustrates learning without interleaving. The diagram below shows how to learn effectively with interleaving. Contextual variation Contextual variation introduces changes in the learning environment or task, requiring adaptation and improving performance flexibility. so how do we know what is a desirable difficulty? And, and, and, and what's not a desirable difficulty? How do we know what's a good difficulty and a bad difficulty? Well the first question to ask is is it one of the three categories I mentioned? Um is it spacing interleaving or contextual variation if it is then uh, it's it's it's probably good it's probably a good thing now there are nuances in how to actually apply this in practice right with with interleaving When do you start interleaving um spaced practice sessions? How long do you space the practice sessions? How long are the practice sessions with contextual variation? How much variation are you going to introduce when to start introducing variation etc? But generally speaking these categories are are the kinds of difficulties that are beneficial Okay, so if it's not one of those categories what do you do And here it's it's a little tough to say For any given kind of difficulty that you might be talking about the question I think you want to ask yourself, is does the difficulty relate to what the learner is learning Or is it just there as kind of a distraction or a kind of busy work or is it just going to make the student kind of annoyed? Any difficulty makes the student exert more effort. The question is, where is that effort going? So in this, uh, font example, I can change the font and the color here to make the text harder to read. And so that's, that means that the student is going to spend more time trying to figure out what the words even are. that's effort that they're spending to try to figure out what the words are And that's, that means that they can't exert effort. that's less effort that they're going to be exerting trying to um, think about what the words mean right? so it's just making things more challenging for the student without any benefit. So I want to leave you The key is that the difficulty must be desirable , meaning it directly relates to the learning material and enhances understanding rather than simply acting as a distraction, busy work, or annoying the student. The question is, where is that effort going? This question helps to distinguish between beneficial challenges and unproductive struggles. This refers to the effectiveness of the difficulty imposed during learning. Simply making something harder doesn't automatically make it better. A student's effort should be directed towards improving understanding and skill, not just struggling with irrelevant obstacles. Desirable difficulty focuses on challenges that force learners to actively engage with the material and improve their understanding, rather than simply increasing the workload without a corresponding benefit. Training Vs. Performance Training is the learning phase—practice, studying, or preparation Performance is when the skills are applied in a real-world setting where the stakes are higher. The key difference is that mistakes are acceptable during training but undesirable during performance. Training methods' effectiveness should be judged by their impact on performance, not just training outcomes. Other resources