Try our FREE bonus challenge: Challenge 5 – Ghost Balloon Rocket (Science & Engineering): Build a balloon rocket and test its speed! Includes Teacher Guide + Student Recording Sheets in PDF and Easel formats. Perfect as a Halloween STEM center, early finisher activity, or extra class fun. 👉 Loved the free sample? Upgrade to the Full Pack for only $4.99 and get 4 more challenges PLUS this bonus freebie here: Halloween STEM Challenge Pack (Grades 2–3 & 4–5) PDF + Easel Color & B/W 🌟 Why T