that her class was scheduled to study plants later in the year, and this was an opportunity for them to investigate questions about plant growth that they had originated and thus were especially motivated to answer. Although she was uncertain about where her students’ questions would lead, Mrs. Graham chose to take the risk of letting her students pursue investigations under her guidance. After all, they had had some experience last year in examining how seeds grow under different conditions. She hung up a large sheet of butcher paper where all the students could see it and said, “Let’s make a list of ideas that might explain what’s happening to those three trees outside.” A forest of hands went up:

Exhibit curiosity, define questions from current knowledge

It has something to do with the sunlight.

It must be too much water.

It must not be enough water.

The trees look different. They used to look the same.

It’s the season, some trees lose their leaves earlier than others.

There is poison in the ground.

The trees have different ages.

Insects are eating the trees.

One tree is older than the others.

Propose preliminary explanations or hypotheses

When the students were satisfied that they had enough ideas, Mrs. Graham encouraged them to think about which of their ideas were possible explanations that could be investigated and which were descriptions. She then invited each student to pick one explanation that he or she thought might be an answer. She grouped the students by choices: There was a “water group”, a “seasons” group, an “insects” group, and so on. She asked each group to plan and conduct a simple investigation to see if they could find any evidence that answered their question. As they planned their investigations, Mrs. Graham visited each group of students

Plan and conduct simple investigation

and carefully listened as they formulated their plans. She then asked each group to explain their ideas to their classmates, resulting in further refinement. Using this quick and public assessment of where they were, she was able to help them think about the processes they were using to address their question and consider whether other approaches might work better.

Gather evidence from observation

For the next three weeks, science periods were set aside for each group



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