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Worksheet Grade 2 Science

The Birdbath at Tollerby Park: A Freeze and Thaw Record

Grade 2 students read an eight-day birdbath chart, count the icy mornings, match ice to cold air, and argue from the record that freezing can be undone.

Objectives

  1. Students will match icy mornings to cold air readings in a two-week record.
  2. Students will explain what made the ice in the birdbath turn to water by afternoon.
  3. Students will argue from the record that freezing and melting undo each other.

Vocabulary

Key words: ice, melt, freeze, solid, liquid, record

Teacher overview

The birdbath on this sheet stands in the fictional Tollerby Park, across the street from a second-grade window, and the chart holds eight school days of morning and afternoon checks. Students count the icy mornings, line those mornings up against the air readings, and then use two rows of the record to argue that the change runs both ways. The misconception the chart is built to catch is the common second-grade claim that melted ice is simply gone: a student holding that idea cannot say where Tuesday afternoon's water came from, and reads Friday as the only day anything stayed in the bowl. Before students reach question 8, point at the Thursday and Friday rows together, where the same water melted part way in the afternoon and was solid again by the next morning.

The Birdbath at Tollerby Park: A Freeze and Thaw Record — Grade 2 Science
Name: ____________________________ Date: ______________

Student Worksheet

Room 5 can see a birdbath in Tollerby Park. The class checked it two times each day. At 8:00 they wrote down how warm the air was. They also wrote what was in the bowl. Then they checked the bowl again at 2:00. Here is their chart.

Morning Air at 8:00, in degrees Bowl at 8:00 Bowl at 2:00
Week 1, Monday 28 All ice Some ice
Week 1, Tuesday 35 Some ice All water
Week 1, Wednesday 41 All water All water
Week 1, Thursday 30 All ice Some ice
Week 1, Friday 26 All ice All ice
Week 2, Monday 38 All water All water
Week 2, Tuesday 31 All ice Some ice
Week 2, Wednesday 44 All water All water
  1. On how many mornings was the bowl all ice at 8:00?
  2. On how many mornings was the bowl all water at 8:00?
  3. Find the four mornings with all ice. Write the highest air number of those four.
  4. Find the three mornings with all water. Write the lowest air number of those three.
  5. On Tuesday of week 1 the air was 35. On Wednesday it was 41. How many degrees warmer was Wednesday?
  6. On Monday of week 1 the bowl was all ice at 8:00. By 2:00 some of it was water. What made the ice turn to water?
  7. On Friday the bowl held ice all day long. Use the chart to tell why.
  8. On Thursday at 2:00 some of the ice had turned to water. On Friday at 8:00 the bowl was all ice again. Does the chart show that this change can be undone? Tell how you know.
  9. Name one more place near your school where you could see water as a solid.

From Water for Schools (waterforschools.org). This material is in the public domain (CC0) and may be copied, edited, and shared freely.

Answer Key
  1. Answer: 4 mornings. Week 1 Monday, Week 1 Thursday, Week 1 Friday, and Week 2 Tuesday all read "All ice" in the 8:00 column.
  2. Answer: 3 mornings. Week 1 Wednesday, Week 2 Monday, and Week 2 Wednesday all read "All water" in the 8:00 column.
  3. Answer: 31 degrees. The four icy mornings read 28, 30, 26, and 31, and 31 is the highest of those.
  4. Answer: 38 degrees. The three watery mornings read 41, 38, and 44, and 38 is the lowest of those.
  5. Answer: 6 degrees. Subtract the two readings: 41 - 35 = 6.
  6. Answer: The air warmed up through the morning. Accept any answer naming warmer air or the sun heating the bowl. The 8:00 reading of 28 was cold enough to hold the ice, and by the middle of the day the bowl was warm enough to melt part of it.
  7. Answer: Friday was the coldest morning on the chart, at 26 degrees, so the bowl never warmed enough for the ice to melt. Accept any answer that points to the low reading.
  8. Answer: Yes. Ice turned to water on Thursday afternoon, and that water turned back to ice by Friday morning, so warming and cooling undo each other. Accept any answer that names both rows as the evidence.
  9. Answer: Accept any real nearby place where water is found frozen, such as a puddle with ice on it, frost on the grass, snow on a roof, or ice cubes in the lunchroom freezer.

Differentiation

Support

Give these students a copy of the chart with the "All ice" rows already highlighted, and limit the sheet to questions 1, 2, 6, and 8. Let them count the highlighted rows with a finger or with counters placed on the page before writing the number.

Extension

Ask students to write what they think the bowl held at 8:00 on the Thursday of week 2, given that the air that morning read 24 degrees, and to name the row of the chart they used to decide. Any answer of all ice with a reason drawn from the colder mornings is correct.

ELL supports

Set an ice cube in a shallow dish of water at the front of the room during the lesson so that "ice," "melt," and "water" stay attached to something students can see. Provide the sentence frames "The bowl held ___ at 8:00" and "The ice turned to water because the air was ___," and allow the counting answers in questions 1 and 2 to be shown on fingers.

Extensions

Set a shallow pan of water outside overnight and check it at the same two times for a week, keeping the same four columns as the Tollerby Park chart. Compare the class pan with the chart on this sheet and ask which mornings matched.