Students consider the following:

• Look in your Science Notebooks at the weight data you have collected for your mini-lakes. What has happened so far?
• What do you predict will happen to the mini-lakes during the next week if they are left uncovered?
• What evidence would need to be collected in order to test your prediction?

Students record their prediction and explain their reasoning and describe the evidence they'll collect to test their prediction on the [Uncovering the mini-lakes] page in their Science Notebooks.

When they finish, students weigh the mini-lakes with the covers still on, and record that weight in the data table and on the graph. They then remove the covers. The weight of the covers should still be included each time students weigh the mini-lakes in the future.