Attention-based learning tasks of modern classrooms require processing of information in working memory. Not much is known about the cognitive processes operating during these tasks. To gain an understanding of the processes that support cognitive functions like learning, we have monitored the activity of the brain waves emanating from the frontal lobes region of a group of high school students working on a series of conceptually-linked tasks using a commercially available electroencephalographic (EEG) headband. Analysis of the EEG recordings revealed an increase in the relative power of gamma and beta as students worked through the tasks, suggesting that they were adding items in the working memory, retaining them, retrieving and reading them out for either use in the tasks or disposal. Remarkably, a decrease in alpha activity indicated that students seem to be attenuating the inhibition of distracting images retrieved from memory to make a larger pool of words available for solving the word puzzle. Such cognitive processing probably increased the load in the working memory as indicated by reduction in theta activity. Lastly, the students increased wakeful attention and alertness by lowering the delta activity. These results provide new insights into the cognitive functions operating during attention-based classroom learning tasks.