Here are some more ideas to get you started.
Engage the fives senses (whenever possible)
Make leaf prints ( paint the leaf and press the print into the journal)
Make leaf rubbings
Trace the items they are looking at
Add leaves into the journal using tape
Count the birds/squirrels/insects etc.
Measure as much of the phenomena as the students can using non standard and standard units of measurement.
Here is a downloadable lesson from John (Jack) Muir Laws and Emilie Lygren book: How to Teach Nature Journaling. All resources shared with permission. "I Notice..., I Wonder...?, It Reminds me of..."
GIVING FEEDBACK here is a fantastic resource from Jack and Emilie
NOTE: You are encourage to spend time in the outdoors Nature Journaling. However, you can also bring nature inside, look out your wonder window, have a refrigerator Safari or even observe a house plant or pet.
What is moving around you? What is on the move in the natural world?
For each type of movement found, determine the cause of the movement. Is it non-contact movement (magnetic and gravitational forces) or contact movement (push and pull)?
Can you determine the type of forces you are seeing: magnetism, muscular force, gravitational force, friction, etc.?
NOTE: This can be used with the Nature Journaling activity at the top of the page.