To encourage students' questions and interest in the bulbs. To learn about students' ideas about the changes they expected to see in the weeks after planting the bulbs.

In this lesson, students observe and draw the bulbs before planting. Without mentioning them by name, we presented two different types of bulbs in each classroom. The types were selected to provide contrasts in size, appearance and plant growth pattern. We asked students to predict what they thought would happen after the bulbs were planted.

Children's predictions about how bulbs would change covered a range of ideas. Some thought the little bulbs would grow into big bulbs. Others asserted that the little bulbs would grow into little plants, and the big bulbs into big plants. Other ideas included: both types of bulbs would turn into flowers, or that the bulbs would shed their outer papery layers as they grew bigger. Some children suggested that the bulbs would not change at all, as they looked like they were already onions.

Less than half of the predictions were supported by comments like "things get bigger/all plants grow" or "bulbs become flowers." The other predictions seemed more like guesses; students did not specify reasons for their predictions.