Two more ideas to make 50 total:

1. Make a Venn diagram comparing/contrasting the characters or setting of the book, or the book with other books, etc.
2. Make a coordinate grid with different traits as the x and y axis and plot the characters on the grid [for instance, the x-axis might be “goodness” and the y-axis might be “intelligence”. A person of average intelligence and goodness would be plotted at (0,0)].

I plan to have Hanu and Rasa do one response activity for each of the 12 weeks of summer vacation, without using the same activity twice. They will certainly read more books than one per week, but I will have them do just one response per week.

Here is the whole list again in one place:

1. Make an advertisement for a product in the book, or which the characters would have liked or needed.
2. Make a six-frame comic of a scene from the book.
3. Write a newspaper story account of an event from the story.
4. Write a biographical sketch of a character or the author.
5. Write a review.
6. Write an essay about the book.
7. Make a book Trailer
8. Make a powerpoint summary of the story
9. Make a powerpoint biography of a character or the author.
10. Come up with a game you can play based on the story or play an actual game that  was played in the book.
11. Write a letter to the main character and the character's reply.
12. Write a different ending for the book. 
13. Pretend you are a talk show host and interview the main character.
14. Create a travel brochure for the setting of the story or scrapbook pages about key characters. 
15. Create a book jacket, including illustrations, an enticing synopsis, author bio, and favorable reviews. 
16. Summarize the book into a comic or story aimed for younger students or your classmates. 
17. Write a news article about an important event from the book. 
18. Write about the decisions you would make if you were the main character in the book. 
19. Dramatize a scene from the story with other students or using puppets. 
20. Post a book review on Share What You're Reading. 
21. Chose two characters from the story and write a conversation they might have. 
22. Write a letter or email to a close friend recommending the book you have just read. 
23. Make a list of new, unusual, or interesting words or phrases found in your book. 
24. Prepare a television commercial about your book. Act out the commercial for your classmates. 
25. Write ten chat room-style questions that could be used to start an online discussion about the book.
26. Or, write ten questions that test other students' understanding of the story. (Make sure you provide a list of answers.) 
27. Explain why you think this book will or will not be read 100 years from now. Support your opinion by stating specific events in the story. 
28. Discuss one particular episode in the story that you remember most. Describe why you think it remains so clear to you. 
29. Write a letter/email to the author of your book. Address it to the publisher and mail it. Or, see if the author has a Web site and email it. 
30. Write a ballad or song about the characters and events in your story. Set the words to the music of a popular song and sing it to the class. 
31. Give a dramatic reading of a scene in the book to your classmates. 
32. Describe in detail three characters from the story. List reasons why you would or wouldn't want to get to know these people. 
33. Design a poster or new book cover depicting the climax of the story. 
34. Write an acrostic poem about the book using the letters in the title of the book or the name of a character or author. 
35. Draw a classroom mural depicting a major scene(s) from the book. 
36. After reading an informational book, make a scrapbook about the topics.
37. Use xtranormal to dramatize a favorite dialogue from the book.
38. Use mediachalk to re-tell a scene from the book.
39. Write a dramatic sketch of a scene from the book, complete with stage directions.
40. Write a persuasive speech that could be used in a debate to convince others of your opinion on a controversial subject from the book. 
41. Make a power-point presentation about the setting of the book, time and place (especially for book with historical or foreign settings)
42. Identify tropes in the story/characters and compare them to similar ideas in other books, movies, etc. (Use tvtropes.org for ideas)
43. How would you act differently than a character in the book if you were in the same situation? Would your philosophy and moral values make you behave or choose differently, and if so, how would that change the outcome of the story?
44. Choose the actors you would cast in a movie adaptation of the book.
45. Write a paper or make a powerpoint describing how you think the time and place the author lived/lives in affected his/her writing style and worldview. Do you think that he/she may have seen things differently if he/she were from modern America?
46. Write an obituary, help wanted, birth announcement, etc., based on the book.
47. Pretend you are a prosecuting or defense attorney and write an argument for or against prosecuting a character who committed a crime.
48. Decide which house each of the main characters would be sorted into at Hogwarts, and briefly explain your decision.
49. Make a Venn diagram comparing/contrasting the characters or setting of the book, or the book with other books, etc.
50. Make a coordinate grid with different traits as the x and y axis and plot the characters on the grid [for instance, the x-axis might be “goodness” and the y-axis might be “intelligence”. A person of average intelligence and goodness would be plotted at (0,0)].