One of the hardest writing assignment for students is the comparison/contrast–how are two items alike and/or how are they different? Perhaps Diffen will eliminate the confusion for those students. Try comparing Steinbeck and his contemporary Hemingway. A science teacher might ask students to compare cells: animal cell vs. plant cell. Or perhaps a health teacher might challenge students to compare/contrast the abdomen and the stomach.
Diffen has the capability of searching Wikipedia to develop a comparison/contrast chart; however, students can also complete the chart with information gleaned from classroom studies or other research tools. Also, check out the categories of predefined subjects for comparison.