Answer :

A group of students.Doesn't obeys teachers.And a girl who is very good in her studies but belongs to a poor family.One day teacher takes class.She asks question " what is 2+2" one student says "22".Teacher angry.Teacher asks a student "get the maths sylabus from next class.student says "i went to all bus stand.They said that they have dulex bus, nondeulex bus,a/c bus,non a/c bus .But they dont have sulabus".All laughed.Teacher again angry.
For some days the brilliant girl didn't come to school.One day the gang of naughty students sees the girl working at a house as servant maid.All asks her why.She said " i love learning .but no money.you have money but you don't learn.please learn".All the bad students turned into a new leaf.
As you have asked this question under the 'English' section, I assume your favorite subject is English. I would suggest doing a play in Biology though, you could pretend to be animals and plants and present the skit on deforestation or something like that. On English, maybe you can go for a skit having excerpts from classics of literature. Or maybe, you could do mini dramas on different authors' life. Best of luck. Hope I helped.

                                                              
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according to my interest, i would do a skit in english. there are many wonderful skits of shakespeare and there many other prominent dramatists  too.if u want to do a skit based on a hollow society then u can opt  for villa for sale by sacha guitry and besides that there are many other interesting subjects too. if u want to do a skit about a historical event the u can choose social.and there are many other important devotional sits in tamil language also.