Evolutionary educational psychology is changing the face of instructional design. By providing us with a base that explains critical aspects of human cognitive architecture, we are able to devise instructional techniques that can work. On the other side of this coin, in the recent past, many popular instructional procedures have failed. Evolutionary educational psychology can explain some of those failures and provide highly effective substitutes.Over the last one or two decades, instructional design recommendations have increasingly emphasized generic skills. Teaching learners generic problem solving skills that can be used to solve a variety of unrelated problems or teaching thinking skills that can be used in any curriculum area provide examples. While it is intuitively plausible that teaching such skills should be useful, evidence that they are teachable is sparse. They certainly are learnable because we all have problem solving and thinking skills, suggesting that generic skills are learnable but not teachable. Why would a skill be learnable but not teachable?Until David Geary’s distinction between biologically primary knowledge that we have evolved to acquire and biologically secondary knowledge that is culturally important but that we have not specifically evolved to acquire, we had no real answer to this question. The distinction between primary and secondary knowledge provides an answer. We all have evolved to easily and automatically acquire those general problem solving and thinking skills that are necessary for survival. We take them for granted because the skills were acquired without being taught or even named. Of course, a skill that has already been learned cannot be taught.In contrast, we do not easily or automatically acquire biologically secondary knowledge. Secondary knowledge encompasses almost everything that is taught in educational and training institutions that were devised precisely in order to assist learners to acquire such knowledge. Secondary knowledge has several characteristics that only become intelligible when considered from the perspective of evolutionary educational psychology.1. Since we have not evolved to automatically acquire biologically secondary knowledge, it is unlikely to be acquired by “immersion” in a suitable environment. Unlike primary knowledge, it requires explicit instruction. Children will learn the biologically primary tasks of speaking and listening simply by immersion in a speaking and listening society. Explicit instruction is unnecessary. In contrast, they are unlikely to learn how to read and write without explicit instruction. Suggestions that students would learn school subjects as easily as they learn outside of school if the same techniques were used are misguided. On evolutionary grounds, the information acquired outside of school is categorically different from the information that students acquire within school. We should not expect the two categories of information to be acquired in the same way.2. Biologically secondary knowledge and skills are domain-specific. We do learn problem-solving strategies, for example, but they are specific to a particular domain. Learning that when faced with an algebraic problem such as, (a + b)/c = d, solve for a, the first move should be to multiply both sides by c, will help a person solve similar problems. It will not be of assistance in solving unrelated mathematics problems or indeed, how to start a car that will not start or how to solve personal problems. Skilled problem solvers in a knowledge rich domain have learned to solve literally tens of thousands of relevant problems and it is that knowledge that results in expertise, not biologically primary, generic skills. Because of that immense knowledge base that is required, it can take many years to acquire high levels of expertise in a given area.3. An immense knowledge base held by a human is analogous to the immense amount of information held in a genome. The structures and functions required by human cognitive architecture can be mapped directly onto the structures and functions that we call evolution by natural selection. Both are examples of natural information processing systems. A genome is analogous to long-term memory; reproduction with its transfer of genomic information is analogous to humans obtaining information by imitating other humans, listening to what they say or reading what they write; random mutation is analogous to random generate and test during problem solving; the epigenetic system has the same function as human working memory. In effect, the structures and functions of evolution by natural selection provide a template for the structures and functions of human cognitive architecture when it deals with biologically secondary knowledge. Over the least two decades, that architecture has been used to generate a considerable array of instructional procedures designed to assist learners to acquire biologically secondary, domain-specific, information. In many cases, instructional effectiveness can be improved by using techniques that reduce an unnecessary working memory load and assist in the transfer of information to long-term memory.In conclusion, evolutionary educational psychology has influenced instructional design by firstly, providing us with a scheme for categorizing knowledge into biologically primary and biologically secondary knowledge. Most knowledge categorisation schemas have not had instructional consequences but this scheme has profound consequences. Biologically primary knowledge can be learned but not taught. In contrast, secondary knowledge that is taught in educational institutions should be explicitly taught rather than left for students to discover. The second way in which evolution by natural selection has influenced instructional design is by providing a template for human cognitive architecture. Both evolution by natural selection and human cognitive architecture provide examples of a natural information processing system and that system, in turn, has generated a variety of instructional procedures designed to reduce working memory load and facilitate the acquisition of information held in long-term memory.