Ahava~Love Assembly

Grade 2 Science Week 14 | Teacher Guide

Grade 2 | SCIENCE

WEEK 14 • TEACHER GUIDE AND ANSWER KEY • DAYS 66–70

Read each lesson aloud with the child and model the worked example before practice. Do not show this key during practice. Accept oral, drawn or written answers where the child cannot yet write the whole answer. On Day 70, read aloud if needed but give no hints.

Week 14 Student Textbook | Week 14 Practice Workbook | Week 14 Teacher Guide | Week 13 Student Textbook | Grade 2 index

Day 66: Testing Strength

Standard: Grade 2 Science Standard 2, 2.2

Practice record: Sample results, printed on the Week 14 Practice Workbook.

Worked example: Why should every bridge cross the same 6-inch gap? Worked answer: So the only difference is the bridge itself.

  1. The folded paper (28 pennies).
  2. 25 more pennies (28 – 3 = 25).
  3. The same paper held far more pennies when it was folded, so changing a material’s shape can make it much stronger. Accept any answer linking the fold to the greater strength.

Teaching note: Results vary. Folded paper usually holds many more pennies than flat paper. Use the observation checklist below.

Hands-on task observation checklist (Test the strength of paper bridges). Check each item you observe. Four or five items shows the child met the task goal; two or three means repeat the task with support.

  • ☐ Child kept the gap the same for every bridge.
  • ☐ Child added pennies one at a time to the middle.
  • ☐ Child stopped counting when the bridge sagged to the table.
  • ☐ Child recorded the count for each bridge.
  • ☐ Child used the counts to name the strongest bridge.

Day 67: Testing Absorbency

Standard: Grade 2 Science Standard 2, 2.2

Practice record: Sample results, printed on the Week 14 Practice Workbook.

Worked example: Which would be better for drying dishes: a cloth towel or a sheet of foil? Worked answer: A cloth towel.

  1. The paper towel and the cloth.
  2. The plastic wrap and the foil.
  3. Plastic wrap or a plastic sheet, because it soaked up none of the water, so rain would run off instead of soaking through. Accept plastic or foil with a reason from the results.

Teaching note: Results vary with the kinds of towel and cloth. Use the observation checklist below.

Hands-on task observation checklist (Test which materials soak up water). Check each item you observe. Four or five items shows the child met the task goal; two or three means repeat the task with support.

  • ☐ Child cut squares of the same size.
  • ☐ Child used the same number of drops on each.
  • ☐ Child waited the same time before tilting.
  • ☐ Child recorded all, some or none for each material.
  • ☐ Child named the most absorbent material from the observations.

Day 68: Flexibility, Hardness and Texture

Standard: Grade 2 Science Standard 2, 2.2

Practice record: Materials and their properties, printed on the Week 14 Practice Workbook.

Worked example: Why is a garden hose made of a flexible material? Worked answer: So it can bend and roll up without breaking.

  1. Rubber and wool.
  2. Wool.
  3. Rubber, because it is flexible so the boot can bend, and it is grippy so it will not slip. Accept rubber with at least one property from the table.

Teaching note: Gather a rubber band, a spoon, a wool sock and a jar so the child can test each property.

Day 69: Choose the Best Material for the Job

Standard: Grade 2 Science Standard 2, 2.2

Practice record: Sample results, printed on the Week 14 Practice Workbook.

Worked example: Why should each cup get the same number of sprays? Worked answer: So the only difference is the material.

  1. The paper towel and the cloth.
  2. The plastic bag and the foil.
  3. The plastic bag, because it kept the cup dry and bent to fit without tearing. The foil also kept the cup dry, but it tore when it bent, so it would not last. Accept the plastic bag with reasons from both columns.

Teaching note: Results vary. Help the child see that the choice must use both columns of data. Use the observation checklist below.

Hands-on task observation checklist (Choose a material for a rain hat). Check each item you observe. Four or five items shows the child met the task goal; two or three means repeat the task with support.

  • ☐ Child used covers of the same size.
  • ☐ Child used the same number of sprays for each cup.
  • ☐ Child checked each cup for water.
  • ☐ Child recorded results for every material.
  • ☐ Child chose a material and gave a reason from the data.

Day 70: Independent Check: Testing Materials

Standard: Grade 2 Science Standard 2, 2.2

Practice record: Testing three mats, printed on the Week 14 Practice Workbook.

Worked example: Is a sponge absorbent? Worked answer: Yes.

  1. The cotton mat.
  2. The wood mat.
  3. The cotton mat, because it soaked up all the water and it bends to fit the floor. Accept cotton with both reasons.

Teaching note: Independent check: read aloud if needed, but give no hints.

Week 14 Student Textbook | Week 14 Practice Workbook | Week 14 Teacher Guide | Week 13 Student Textbook | Grade 2 index

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