Lesson plan Kindergarten Science
Dew on the Grass at Goldfinch School: A Morning Watch Lesson
A kindergarten lesson across four short sittings where the class checks the grass on three mornings, charts which ones had dew, and finds where the dew goes.
Objectives
- Students will observe and record whether the school grass is wet on three mornings.
- Students will sort three mornings into dew and no-dew groups and count each group.
- Students will explain that dew comes from the air and goes back into the air by noon.
Vocabulary
Key words: dew, cool, clear, cloudy, wet, dry
Teacher overview
Goldfinch School is a fictional school, but the grass in this lesson is the strip outside your own door. On three mornings in a row the class walks out early, presses a dry paper towel on the grass, checks whether the blacktop beside it is wet or dry, and records the morning on a chart along with cool or warm and clear or cloudy. On the third day the class returns to the same grass at noon and finds it dry. The chart then gives students three real mornings to sort and compare, and the noon check gives them the second half of the story.
The misconception this lesson exists to correct is the belief that dew is rain that fell quietly during the night, which many kindergartners say the first time they feel wet grass under a clear sky. The evidence that settles it is close at hand: on a dew morning the grass is soaked while the blacktop two steps away is dry, and rain would have wet both. Say plainly that the water came out of the air onto the cool grass, and that by noon the warm air takes it back. Run the three checks on days the forecast shows no rain, since a rainy night makes the comparison impossible.
Procedure
First morning check (6 min): Take the class outside within the first twenty minutes of the day. Have two students press a dry paper towel flat on the grass and hold it up so everyone can see whether it came back wet. Walk four steps to the blacktop and have two more students press a second towel there. Ask the class to say cool or warm and clear or cloudy, then write the morning on an index card with a wet or dry mark for the grass, a wet or dry mark for the blacktop, and the two weather words.
Second morning check (6 min): Repeat the same routine with different students holding the towels, and read yesterday's card aloud before going out so the class knows what it is comparing against. When the card is filled in, tape both cards side by side on the chart paper where every student can see them.
Third morning check (6 min): Repeat the routine a third time and tape up the third card. Ask the class to look at all three cards together and say what they notice about which mornings had wet grass. Write two student sentences on the chart in their own words, such as "the cool one was wet" or "the cloudy day was dry," without ruling on either yet.
Noon return and pattern session (12 min): Walk the class back to the same grass just before lunch and have a student press a fresh towel on it. Ask where the water on the grass went, and accept the answers that come. Back inside, sort the three cards into a dew pile and a no-dew pile, count each pile out loud, and ask which pile has more cards. Then hold up the wet grass card and the dry blacktop mark beside it and ask the class one question: "If rain fell last night, would the blacktop be wet too?" Say the explanation plainly once the class answers: the water came out of the air onto the cool grass overnight, and the warm air took it back by noon. Close with a thumbs poll on "Did rain fall last night?" If more than a few thumbs go up, walk the class back to the dry blacktop and ask the question again there.
From Water for Schools (waterforschools.org). This material is in the public domain (CC0) and may be copied, edited, and shared freely.
Differentiation
Support
Let these students carry and press the towels every morning so the wet-or-dry judgment is something they feel rather than something they watch. During the sort, hand them the three cards one at a time and name the two piles out loud again before each card is placed.
Extension
Ask these students to add a fourth check on their own, choosing a new surface such as a window, a metal railing, or the slide, and to report whether it matched the grass or the blacktop. Have them predict, before the next morning check, whether there will be dew, and then say what they used to decide.
ELL supports
Pre-teach dew, wet, dry, cool, and clear by passing around one damp towel and one dry towel while each word is spoken and written beside a small drawing. Accept holding up the wet towel or the dry towel as a full answer during every check, and provide the sentence frame "The grass was ___ this morning" with both words available on cards.
Extensions
Set a clean metal spoon outside overnight and bring it in with the morning check so students can see that the same water collects on other cool things, not only on grass. Keep the three cards on the wall and add one new card each week for several months, then look back at the row and ask the class which time of year has been bringing the most dew mornings.