7th grade integrated science

Standard III, Objective 2

Title: What do cells need?

Description: Students will write a creative document about the needs of cells are met by tissues and organs of the body

Materials: text book/internet, computer (for word processing, optional)

Time Needed: 90 minutes

Prior Knowledge: This activity would be best at the end of the unit when students know about the tissues and organs. It could be used for summative or formative assessment of the unit.

Procedures:

1. Tell student that they are going to write a RAFT paper. RAFT stands for:

Role: Who (or what) you are.

Audience: To whom are you writing?

Format: What form will your writing take?

Topic: What subject are you writing about?

2. Share an example with the students. You may wish to project or make an overhead of this one:

R = cell

A = tissue or organ

F = letter

T = I need help

Dear Heart,

I am a cell living in the body of Todd, a seventh grade student at______Middle school. Todd takes good care of himself but he needs some help. I am a cell living in his muscles and, boy, some days he exercises and I need more oxygen to be comfortable.

I was hoping that you might pump more blood my way and make sure you send it to the lungs for oxygen first. When it gets to me, I feel like I have just been given a new lease on life. I get rid of some wastes and combine that oxygen with food to release more energy and I could just keep on moving his body as long as he wants. In fact, I feel like the energizer bunny when that happens. I hope you will consider this request, after all, you are part of the body and when he exercises, it helps you, too.

Have a great day,

George, a muscle cell

3. The following table shows some suggestions for RAFT papers. You may encourage students to create their own or you may wish to limit them to this table.

4. Make sure that student have a copy of the rubric. Point out to them that including the need of the cell and the way it can be met are important.

5. Have willing students read their work out loud or if time permits. You may wish to have the students respond to each other’s work or use the rubric below to grade the assignments.

suggestions

Role Audience Format Topic

Bone cell / Muscles, digestive system / Letter / Help me grow, stay strong
Heart cell / Blood, lungs, blood vessels / Letter / I need a workout, feed me, relax
Brain cell / mouth, muscles, nerves / letter / I need breakfast, wear your bike helmet
Stomach cell / Esophagus, intestine, gall bladder / letter / Slow down, feed me, add enzymes,

Rubric

Six Traits Peer Response Chart
Author’s name:______Your name:______
Assignment: RAFT assignment / 5 / 4 / 3 / 2 / 1
Ideas and Content
The writer describes the situation, giving specific details about the cell and it’s needs. Facts are accurately stated. The cell should correctly describe what it needs from the tissues or organs it is writing to.
Organization
The response is orderly and organized into paragraphs. There is an introduction, a body, and a conclusion.
Voice
The writer directly addressed the audience. The language is natural and makes it convincing and interesting to read.
Word Choice
Words used are specific and accurate. They are not confusing.
Sentence Fluency
Sentences are complete and are logical. They show how the ideas are interrelated.
Conventions
Grammar, spelling, and punctuation are correct and contribute to clarity.
The most interesting or convincing part was. . .