Here you have an excellent video made by two nice guys!
If you want to follow it reading here you have the script:
Emma: Welcome to our English Language Lesson. I am Emma
Thomas: And I am Thomas. Today we will look at the simple present tense.
Emma: We will look at positive sentences, the negative sentences and the questions
Thomas: Two examples of positive sentences are 'I am Thomas' and 'She is Emma'
Emma: Yes, I am Emma, I am 14 years old and I am a student. He is Thomas, he is 12 years old and he is a student. We can make these negative sentences by using the word not.
Thomas: I am not Emma, I am not 14 years old and I am not a girl
Emma: I am not Thomas, I am not 12 years old and I am not a boy. If you want to make a question just bring the verb to the front of the sentence, like this; Am I a girl?
Thomas: Yes you are
Emma: Am I 14 years old?
Thomas: Yes you are
Emma: Am I Susan?
Thomas: No you are not, you are Emma.
Thomas: That's all for this lesson. See you next time.
Emma & Thomas Bye
Emma: You can go to our Blogsite at http://EasyEnglish4You.Blogspot.com to let us know what you think of this lesson.
Thomas: And you can go to kwlc24.googlepages.com for a copy of this script and notes and exercises on the Simple Present (Active) tense.