Passed On, and Not Quite the Same
A 55-minute Grade 3 lesson on analysing data to show that traits are inherited from parents and still vary within a group.
Passed On, and Not Quite the Same is a free 55-minute Grade 3 science lesson plan for Common Core standard 3-LS3-1 — use data to show traits are inherited and still vary within a group. It is timed across 5 sections, gives the exact wording to use where the wording carries the mathematics, names 3 misconceptions with the teaching move that addresses each, and ends with an exit ticket and a printable worksheet with its answer key.
- Grade:
- Grade 3
- Length:
- 55 minutes
- Standard:
- 3-LS3-1
Grade 3 · Life Science
3-LS3-1
Analyze and interpret data to provide evidence that plants and animals have traits inherited from parents and that variation of these traits exists in a group of similar organisms.
Objective
Students will be able to separate a trait that is shared from one that varies within the same group.
Students are successful when they can
- Names a trait shared by every member.
- Names a trait that varies between them.
- Says which is evidence of inheritance.
What you need
- Sunflower height data from one seed packet
- Photographs of one litter of puppies
- The printable practice sheet linked at the end of this plan
The lesson
Warm-up
5 min- Show five sunflowers from one packet and ask what is the same about all of them.
- Then ask what is different.
Teach — shared, varying, and caused
14 min- List what every plant shares: yellow flowers, thick stem, same leaf shape.
- List what varies: 139 cm to 155 cm in the same bed.
- Say what both show: the traits came from the parent plants, and they vary.
- Add the third case: the shady bed grew far shorter, which the surroundings caused.
- Ask how to tell variation from an environmental effect: was the surrounding the same?
- Say the rule: same conditions and still different means variation.
“Same conditions? Then the difference is variation.”
Investigate — measure a group
19 min- Groups measure a trait across ten individuals from one source, such as leaf length or seed size.
- They record every measurement and find the range.
- They name a trait every one of them shares.
- They say whether the conditions were the same for all ten.
Independent practice
14 min- Students complete the 'Passed On, and Not Quite the Same' page.
- Check the three groups are kept apart.
Close
3 min- Ask which trait in the class data varied most.
What goes wrong, and why
Each of these is a reasoning error rather than carelessness. The fix addresses the reasoning.
Thinks inherited means identical.
Why: Inheritance sounds like copying.
Fix: Five plants from one packet ranged 139 to 155 cm. Inherited and varying.
Calls every difference environmental.
Why: The environment is the recent lesson.
Fix: Same bed, same soil, still different. That is variation.
Measures one individual.
Why: One is quicker.
Fix: Variation cannot be seen in one. Measure ten.
If they are not there yet
- Five individuals rather than ten.
- A table with the shared trait already named.
If they finish early
- Find a trait with almost no variation and say why.
- Compare variation in two different groups.
- Say what would show a trait is not inherited at all.
Exit ticket
Five sunflowers from one packet grew 139 to 155 cm in the same bed. What does that show?
What to look for: The height trait is inherited and varies between individuals, since conditions were the same. Calling it environmental means the same-conditions check needs another run.
Printable practice for 3-LS3-1
Free to print and copy, answer key included. Each sheet can generate a fresh set of problems for a retake.
- Passed On, and Not Quite the SameSort each one into the right group.
Questions about Passed On, and Not Quite the Same
How long does the Passed On, and Not Quite the Same lesson take?
55 minutes, split across 5 timed sections: warm-up 5 min, teach 14 min, investigate 19 min, independent practice 14 min, close 3 min. The minutes are stated per section and add up to the stated length, so the plan can be cut or extended at a section boundary rather than abandoned halfway.
Which standard does Passed On, and Not Quite the Same teach?
3-LS3-1 — 3-LS3-1, Life Science for Grade 3: “Analyze and interpret data to provide evidence that plants and animals have traits inherited from parents and that variation of these traits exists in a group of similar organisms.” In plain terms, use data to show traits are inherited and still vary within a group.
What do I need to teach this lesson?
Sunflower height data from one seed packet, photographs of one litter of puppies and the printable practice sheet linked at the end of this plan. Everything listed is either ordinary classroom equipment or a free printable from this site — there is nothing to buy and nothing to prepare beyond photocopying.
What mistakes should I expect in this lesson?
Three, each a reasoning error rather than carelessness: thinks inherited means identical; calls every difference environmental and measures one individual. The plan gives the thinking behind each one and the teaching move that addresses the thinking rather than the symptom.
How do I know whether the lesson worked?
The exit ticket asks: “Five sunflowers from one packet grew 139 to 155 cm in the same bed. What does that show?.” The height trait is inherited and varies between individuals, since conditions were the same. Calling it environmental means the same-conditions check needs another run. That tells you whether the class needs a reteach or a thirty-second conversation before you plan tomorrow.
Is there a worksheet to go with Passed On, and Not Quite the Same?
Yes — 1 printable 3-LS3-1 worksheet, linked at the end of the plan and free like the rest of the site. Each one comes with an answer key and 25 versions, so the practice after the lesson can be a different paper on every desk.
Is Passed On, and Not Quite the Same free to use?
Yes. The plan, its printables and their answer keys are free to read, print and photocopy for your own class, with no account and no email capture. It was last reviewed on 8 September 2026. Please do not resell it or republish it as your own.
Last reviewed 2026-09-08. Aligned to 3-LS3-1 of the Next Generation Science Standards.