This article discusses the application of vector models for the preliminary analysis of students' free-form answers. Vector representations of words and documents were obtained using word2vec, doc2vec, and BERT models. The similarity between the answer given by the student and the correct answer was determined using the cosine measure. It was found that vector models allow identifying obviously incorrect answers with sufficient accuracy. For answers that are close in wording, an additional verification step is proposed. Using word2vec, binary classification of answers to certain questions was performed, and accuracy, precision, recall and F1-measure estimates were given.