Hidden Family Ties

About this resource

A squishy blob glued to a dock squirts water when you poke it. It has no head, no eyes, no legs, and no bones. Yet scientists say its family ties are a big surprise. Who is the sea squirt related to — and how could anyone tell? Compare how animals develop — embryos and larvae reveal family ties that adult bodies hide. In this one-week, 5-level Embryo Development Evidence unit for middle school science (NGSS MS-LS4-3), students investigate a real mystery, then use their evidence to crack the case.

Hidden Family Ties is part of Science Unlocked, a series of mystery-driven lesson sets. Every set opens with a real, surprising phenomenon, builds the science one level at a time, and ends with students solving the mystery in a claim-evidence-reasoning (CER) write-up.

Topics: evidence of evolution, claim evidence reasoning (CER), science phenomenon, review games.

What's included

• Teacher Deck (85 slides, PowerPoint). Answers are highlighted on the slides. Speaker notes tell you what to say and do, what to watch for, and how to support students or push GT students further. Prep slides and answer keys are hidden, so they skip during a slideshow.
• Interactive Student Deck (52 slides, PowerPoint + PDF). Students type in boxes, drag cards and check marks, and rate their confidence. Assign one copy per student in Google Classroom or your LMS.
• Google Slides versions of both decks. Click a button in the Google Slides Links PDF to make your own copy in Google Drive.
• Teacher Guide (23-page PDF). The standard, a week at a glance, a materials list, misconceptions to watch for, a run-of-show for every level, answer keys and sources.
• Student Printable (17-page PDF + a low-ink greyscale copy). The same tasks on paper in 12 pt type, for students without devices, sub days, or anyone who learns better with a pencil. Slide numbers match the Student Deck.
• Self-grading digital activity. SCORM 2004 and SCORM 1.2 packages for an LMS that accepts SCORM uploads, a web package, and a single HTML file that opens in any browser. Notes, sorts, matches, tables and multiple-choice items grade themselves, and students get a copy-and-paste backup of their work. A 2-page teacher quick start is included.
• Two whole-class review games that open in any browser: a Jeopardy-style game (6 categories, 30 clues) and Trashketball, where teams answer on whiteboards and then shoot for points.
• Kahoot! and Blooket import files. 48 review questions, one file per level plus an all-levels file, with a printable answer key.
• Start Here guide, HTML & SCORM how-to guide and Terms of Use, so you know which file to open first.

The 5 levels (about one 45–50 minute class each)

1. Who’s Related? Embryo, larva, adult, why compare young forms. Key activities: Sea squirt mystery, Embryo/Larva/Adult sort.
2. Embryo Line-Up. Analyze pictures of 4 vertebrate embryos, shared features, Haeckel caution. Key activities: Embryo pictures, label an embryo, Embryo vs. Adult data table.
3. Same Start, New Endings. What arches, tails and limb buds become, patterns leads to relationships. Key activities: Match It, embryo-feature tree, vertebrate pattern sort.
4. Larva Lab. Investigation: are barnacles mollusks or crustaceans? Key activities: Live brine shrimp larvae (or virtual views), data table, Lab Conclusion CER.
5. Crack the Case. Stretch HS-LS4-1: many lines of evidence (embryos, DNA). Key activities: Final clue (sea squirt larva), place it on the tree, Stretch CER, final CER.

Built for real classrooms

• Every level follows the same routine: "I can" targets with a confidence check, a warm-up, copy-it notes with a word bank, hands-on practice, a checkpoint students must pass to unlock the next step, and an exit ticket. A 10-item Mini Quiz wraps up the week.
• Level 1 opens with a Power-Up on the earlier-grade ideas this standard builds on (1-LS3-1, 3-LS1-1, 3-LS3-1, 4-LS1-1).
• The last level includes a high school Stretch (HS-LS4-1) that every student tries and advanced students can take further.
• Hands-on lab (Larva Lab: Meet a Nauplius). Student materials list: Brine shrimp larvae, hatched 1–2 days ago (your teacher set them up); Flashlight (steady mode); Dropper, petri dish or depression slide; Hand lens or microscope (lowest power); Station cards A–D (larva pictures); Paper towels. Safety notes are on the slides and in the Teacher Guide.
• Support is built in: word banks, sentence starters and support notes on the slides, plus GT extensions.

Standards

• NGSS MS-LS4-3: Analyze data to compare patterns in the embryological development across multiple species to identify relationships not evident in the fully formed adult anatomy.
• SEP: Analyzing and Interpreting Data · DCI: LS4.A · CCC: Patterns
• Stretch: HS-LS4-1
• CCSS connections: RST.6-8.1, RST.6-8.7, RST.6-8.9

Try the digital activity first

• Not sure the self-grading activity will work in your LMS? Download the FREE HTML & SCORM Sample and test it with your students before you buy.

Save with a bundle

• Evidence of Evolution (3 sets)
• Middle School Life Science (21 sets)
• Science Unlocked Mega Bundle (all 89 sets)

Teach next

• The Fossil Forecast (MS-LS4-1)
• The Whale’s Hidden Hand (MS-LS4-2)

More from Mystery Lab Learning

• See every Science Unlocked set, and follow to hear when new ones are added, at Mystery Lab Learning.

Good to know

• The illustrations in this resource were created with AI image tools, and AI tools helped draft the lesson text. Every slide, answer key and lab step was then fact-checked against the sources listed in the Teacher Guide and proofread.
• Kahoot!, Blooket, Jeopardy!, Google Slides and PowerPoint are trademarks of their owners. This resource is not affiliated with or endorsed by them.
• License: one teacher, for use with their own students. Please buy an additional license for each colleague who uses it.