What the Structure Is For is a free printable Grade 4 science worksheet on how internal and external structures support survival, growth and reproduction, aligned to NGSS performance expectation 4-LS1-1. It prints 2 questions with an answer key on its own sheet of paper, in 25 versions that each ask different questions, so no two students in the class work from the same page. Print it from the browser or download it as a PDF — no account, no email.
Set 2 of 25 · the same problems every time you open this link.
Set 1 has all 25 in a single PDF. All 25 sets ask different questions.
What the Structure Is For
4-LS1-1
NameDate
Draw a line from each structure to what it does.
1.Draw a line from each one to its match.
A cactus's thick waxy stem
A rose's thorns
A duck's webbed feet
A bird's hollow bones
A.Keep it light enough to fly
B.Stores water and stops it drying out
C.Stop animals eating the stem
D.Push against the water to swim
2.Draw a line from each one to its match.
An owl's large eyes
A fish's gills
A seed's hard coat
Lungs
A.Take in oxygen from the air
B.Gather enough light to hunt at night
C.Take in oxygen from the water
D.Protects the tiny plant inside until it sprouts
LessonPrint · 4-LS1-1 · Set 2 · free to copy for classroom use
Answer key — What the Structure Is For
Set 2. Prints on its own sheet.
1.1. A cactus's thick waxy stem — B (Stores water and stops it drying out) 2. A rose's thorns — C (Stop animals eating the stem) 3. A duck's webbed feet — D (Push against the water to swim) 4. A bird's hollow bones — A (Keep it light enough to fly)
2.1. An owl's large eyes — B (Gather enough light to hunt at night) 2. A fish's gills — C (Take in oxygen from the water) 3. A seed's hard coat — D (Protects the tiny plant inside until it sprouts) 4. Lungs — A (Take in oxygen from the air)
Last reviewed 2026-09-05. Aligned to 4-LS1-1 of the Next Generation Science Standards.