November 9, 2015
By Dwayne Slobodnick

Lesson plan

Sink or Float with the Cookie Monster

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Students will be able to use the scientific method when doing an experiment.

(5 minutes)
  • Explain to the students that they will do an experiment today, and that they will watch a couple of videos to help them learn new words.
  • Play the Science Pirates Songs - Hypothesis Song, and write the words "question," "hypothesis," "test," and "observation" on the board.
(10 minutes)
  • When the song is over, ask the students if they can explain what the words you wrote down mean.
  • Discuss the meaning of the words with the students, and tell them that they are scientists today, and that they will ask questions, hypothesize, test predictions, and make observations.
  • Tell them that their first experiment is to help Cookie Monster do an experiment.
(15 minutes)
  • Play Sesame Street Science: Sink or Float?. This video is interactive and the viewer makes the decision about what to do next.
  • When it is time to choose an object to test and make a hypothesis in the interactive video, ask the students to vote. Then select what the students want.
  • When the video is over and you tested all the objects, ask the students what surprised them during the experiment.
  • Explain to the students that they will now do their own experiment in small groups.
  • Show the students the Sink or Float Observation worksheet, and tell them to simply draw pictures of their objects for the hypothesis and observation sections.
(15 minutes)
  • Put the students into groups of 3 or 4 and give each group tubs of water and the objects to test.
  • Tell the students that they need to make a hypothesis and predict if the object they test will sink or float before they put it in the water. Then tell them to put it in and observe what happens.
  • Remind the students to take turns putting things in the water.
  • Hand out the Sink or Float Observation worksheet and tell the students to begin their experiment.
  • Enrichment:To challenge students, have students explain or write on the worksheet why they made the prediction they made.
  • Support:Students do not have to fill in an observation worksheet. The teacher can have a conversation with the student to assess their understanding.
(5 minutes)
  • During the experiment, walk around and listen to student conversations and ask them questions to push deeper understanding.
  • Look over student worksheets to check their understanding.
(10 minutes)
  • Bring the students together.
  • As a class, go over the results of the experiment.
  • Ask the students if they were surprised by any of the observations they made.
  • Ask the students to share any questions they still might have and write them down on chart paper.

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