asking students about some obscure matters or riddles has a great value in developing their abilities and sharpening their brains. the best way to use this method is to present the unclear subject to all students, then the teacher should give them some time to review the available information to conclude the result, then to give the solution of the matter or question asked. the sunnah of the prophet muhammad (peace be upon him) is rich with this educational technique. 1- narrated ibn omar: allah's apostle (peace be upon him) said, "amongst the trees, there is a tree, the leaves of which do not fall and is like a muslim. tell me the name of that tree." everybody started thinking about the trees of the desert areas. and i thought of the date-palm tree but felt shy to answer the others then asked, "what is that tree, o allah's apostle?" he replied, "it is the date-palm tree." al-baghawi said, the imam said: this shows that a scholar may ask his students riddles or obscure questions to test their degree of knowledge. ibn hajar (may allah have mercy on him) said: this hadith has many lessons. it teaches us that the scholar should test the mentality of students provided that he clears to them the obscurity later. it also shows encouragement to seek knowledge and activate the brain. the teacher should choose subjects that he will suggest to his students, also he should let them discuss them among themselves and with him then to give their opinion or final answer. this is reflected in “everybody started thinking about the trees of the desert areas.” it is obvious that they tried their best to think of the matter to find the answer and they did not just wait for the prophet’s answer. al-hafiz said: they thought about the trees of the desert, each of them thinking about a certain one but they overlooked the date-palm trees. if we contemplate over the matter that the prophet muhammad (peace be upon him) said, we will find that it activated their thinking and promoted them to seek the answer, it is a sort of brainstorming. this way they are more anxious to know the right answer from the prophet (pbuh) after they spent some time in thinking but they couldn’t guess the name of this tree. another important point is that the obscure matter or riddle should imply an idea or establish a point of view for students. this is reflected in linking the date-palm tree with the muslim. what is the value of this question? al-hafiz ibn hajar explains it by saying: the value of the date-palm tree exists in each of its parts. it is valuable in all its stages, when it produces fruits till it turns dry. even when it is dry, we may use all its parts. even the kernel of dates is important as it can be used to feed animals, also the fiber and floss can be used in making ropes, etc. the blessing of the muslim is the same, it is general and on all levels. his value is not only for himself but for others as well, even after his death if he leaves a good legacy or knowledge behind him for the benefit of mankind such as muslim scientists and scholars who left their books and knowledge for generations behind them. this is a very important educational method and effective in teaching students if it is used well by teachers. yet, the teacher should avoid complex unresolved matters. he should not overburden or incapacitate his students. rather, he should approximate the matter by giving hints or leads to help them reach the right answer. this is reflected in another narration of the hadith. in the narration it is mentioned that the prophet (peace be upon him) had spadix of the palm tree in his hands. mujahid said, "i accompanied ibn umar to madina and only heard him relate one hadith from the messenger of allah, peace be upon him. he said, 'we were with the messenger of allah, peace and blessings of allah be upon him, when the spadix of a date-palm was brought to him. he said, 'there is a tree which is like the muslim.' i wanted to say that it was the palm-tree, but i was the youngest of the people so i kept silent. the prophet said, 'it is the palm-tree.'' al-hafiz ibn hajar said: the teacher or instructor should do not exaggerate in obscurity; he rather should give clues to help listeners find a way that leads them to the answer. the more he approximates it to their minds, the more they will appeal to listen. summary: 1) the importance of this method in activating the mind, sharpening the brain and widening knowledge. 2) using these matters in ascertaining certain important ideas in the minds of listeners.