In the context of the big data era, a model for mining Civics elements using convolutional neural networks is proposed to address the problems of poor interaction between teaching practice and Civics elements. The use of this model for the mining and teaching practice of Civics elements allows teachers to make changes to the design of teaching contents in real time in order to maximize the integration of lecture contents and Civics elements. In addition, in order to improve the effectiveness of the model, an improved model with A-Softmax algorithm and softmax output layer fusion is proposed, and the experiment proves that the improved model has a certain degree of improvement in performance.