A science notebook entry is stronger when it keeps observation and explanation in separate lanes. If a shadow looks longer later in the day, first record exactly what changed; then use what you know to suggest why it might have changed.
Write only what you noticed
Describe what you could see or measure before adding a cause. You might note that a pencil’s shadow was short near midday and longer later, using the same pencil and the same spot on the desk. That is an observation; “the Sun moved closer” is an explanation, and it needs evidence.
Keep the comparison fair
If you are comparing shadows, keep the object and its position the same and record the time of each observation. Changing several things at once makes it harder to tell what could account for the difference. A simple two-column table—time and shadow length—can make the pattern easier to notice.
Connect evidence to an idea
Now explain the pattern using evidence from your notes and a science idea you have studied. You could say that the shadow changed length as the Sun’s apparent position in the sky changed, pointing to the measurements you recorded. Across classes 1–10, the explanations grow more detailed, but the useful starting point stays the same: say what you saw, show the evidence, then explain.