[middlemath]

I am getting ready to start proportions next week amd am in search of a fun, hands-on activity that results in some nice student work to put up in the room. I teach seventh grade math. Anyone have any ideas of what works either as an introductory activity or an activity I can do once they understand how to solve a proportion?

[Margaret916]

is a great book usiing proportion.

[Jola]

I teach elementary, so I'm not sure of the details you have to teach about proportion, but here is an activity I have done in the past....the kids loved it.

I took a simple clip art (black line picture or coloring book) and blew it up to a full sheet of paper. On the back of the paper I drew out a one inch square grid and numbered it. (Make a copy first.) Cut the picture apart into one inch squares - part of the picture on front, a number on back. Have students pick a square and recreate it on a larger square...whatever size you specify. They have to write the number on the back and it needs to be oriented the same way so the square doesn't get turned around. Let them glue the larger squares on bulletin board paper in order to discover what the picture is. The suspense was so fun. They created a giant picture and didn't even know what it was until the end. You can then post a copy of your original picture and the enlarged one side by side.

I'm sure you can think of a way to label this, discuss it, and ask the students questions that will illustrate the components of proportion you are teaching.

One year I did this before teaching about the size and distances of the planets so they would understand the concept of proportion. Another year I did it with decimals as the numbering system on the back as part of our math unit on decimals. (row one was .00 thru .09, etc. )

[d_ee]

almost every resource I look at to get proportion ideas has the famous "shadow problem" so why not take them outside on a sunny day. Measure the student height, measure the student shadow. Measure the shadow of a tree or building or pole standing next to the student and find the height of the object by a proportion. Student height is to student shadow as object height is to object shadow

[Mathzilla]

This is too late to help Middlemath, but I did a fun activity with my 7th graders last year. You use rubber bands to create a tool to draw a scale drawing of a master. You start with a simple geometric shape so it's easy to trace. You actually take 2 rubber bands and link them with a knot. You hold one side of the rubber band on a stationary point on the paper some inches left of the drawing. Pulling the rubber band taut, you slide the knot along the original picture, while you put a pencil in other the loop of the rubber bands, pull it taut, and the pencil follows the movement of the knot and creates a scale picture.

It's actually very easy. Once the kids do it once, they can try it again with all sorts of pictures (SpongeBob, etc.). Then they can measure corresponding sides of the original and the traced picture and create a scale for the pictures. They can redo the experiment using smaller or larger rubber bands, and see how the sizes differ. They can create and test hypotheses about what will produce different size shapes.

It's quite fun.