How to Make Your Own Mystery Class Graph


VERY IMPORTANT: Your graph must be tall to prevent overcrowding. Follow these instructions carefully!

A. Graph Paper
Use 2 1/2 sheets of 8 1/2 x 11 graph paper. This will allow one inch per day-length hour.

B. Vertical Axis
Tape 2 1/2 graph sheets together, so the resulting graph is 27 1/2" tall. The left edge of your graph (the 27 1/2" side, which is the vertical axis) will indicate day length hours. Allow space for 24 day length hours in total. At the lower left, begin with 0 hours of day length. Go up the vertical axis to 24 hours, and allow 4 squares for each hour.

C. Horizontal Axis
The bottom of your graph (the 8 1/2 inch side, which is the horizontal axis), will denote the dates of your Monday readings. Mark 11 weeks along the bottom, allowing three squares per week. Write the following dates for your Friday readings along the bottom of the graph:
Sample Mystery Class Graph


For guidance in making your own graph, see our ready-made version:

See sample:
(doc or pdf )

Classroom Wall Graph

Teacher Cathie Plaehn
Wisconsin Fifth Grade teacher and Journey North Teacher-Advisory Board member.

For a large classroom wall graph, we recommend teacher Cathie Plaehn's example. She makes a huge 3 x 3 wall graph using butcher-block paper. Each student-group makes their own individual graphs, but the entire class plots data on the wall graph. Cathie shares this and other tips which are especially helpful early in the season. See how she helps her students calculate photoperiods.