Unsupervised Environment Design (UED) is a paradigm for training generally capable agents to achieve good zero-shot transfer performance. This paradigm hinges on automatically generating a curriculum of training environments. Leading approaches for UED predominantly use randomly generated environment instances to train the agent. While these methods exhibit good zero-shot transfer performance, they often encounter challenges in effectively exploring large design spaces or leveraging previously discovered underlying structures, To address these challenges, we introduce a novel framework based on Hierarchical MDP (Markov Decision Processes). Our approach includes an upper-level teacher's MDP responsible for training a lower-level MDP student agent, guided by the student's performance. To expedite the learning of the upper leavel MDP, we leverage recent advancements in generative modeling to generate synthetic experience dataset for training the teacher agent. Our algorithm, called Synthetically-enhanced Hierarchical Environment Design (SHED), significantly reduces the resource-intensive interactions between the agent and the environment. To validate the effectiveness of SHED, we conduct empirical experiments across various domains, with the goal of developing an efficient and robust agent under limited training resources. Our results show the manifold advantages of SHED and highlight its effectiveness as a potent instrument for curriculum-based learning within the UED framework. This work contributes to exploring the next generation of RL agents capable of adeptly handling an ever-expanding range of complex tasks.