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Aligning Graph Neural Networks (GNNs) and Large Language Models (LLMs) benefits in leveraging both textual and structural knowledge for Text-attributed Graphs (TAGs) learning, which has attracted an increasing amount of attention in the research community. Most existing literature assumes a uniformly identical level of learning difficulties across texts and structures in TAGs, however, we discover the $\textit{text-structure imbalance}$ problem in real-world TAGs, $\textit{i.e.}$, nodes exhibit various levels of difficulties when learning different textual and structural information. Existing works ignoring these different difficulties may result in under-optimized GNNs and LLMs with over-reliance on either simplistic text or structure, thus failing to conduct node classifications that involve simultaneously learning complex text and structural information for nodes in TAGs. To address this problem, we propose a novel Curriculum GNN-LLM Alignment ($\textbf{CurGL}$) method, which strategically balances the learning difficulties of textual and structural information on a node-by-node basis to enhance the alignment between GNNs and LLMs. Specifically, we first propose a text-structure difficulty measurer to estimate the learning difficulty of both text and structure in a node-wise manner. Then, we propose a class-based node selection strategy to balance the training process via gradually scheduling more nodes. Finally, we propose the curriculum co-play alignment by iteratively promoting useful information from GNNs and LLMs, to progressively enhance both components with balanced textual and structural information. Extensive experiments on real-world datasets demonstrate that our proposed $\textbf{CurGL}$ method is able to outperform state-of-the-art GraphLLM, curriculum learning, as well as GNN baselines. To the best of our knowledge, this is the first study of curriculum alignment on TAGs.