Welcome to "Probe Path Jump", a Grade 2 Add/Subtract on a Number Line mission at the Seedling warm-up level, staged in a space scenario. The mission opens with a hands-on prompt: "Start at 7. Make 6 hops of size 1. Place the END on the number line." Students work with the numbers 7, 6, 1 and reach a final answer of 7 across 3 guided steps.
Behind the story, this lesson builds add/subtract on a number line understanding aligned to CCSS 2.MD.B.6. The key strategy is: 7 + 6 = 13.
A common misconception this page surfaces is: Jumping in the wrong direction for subtraction. Plus = right (toward bigger). Minus = left (toward 0). Picture the arrow before the first hop. The adaptive Socratic hints move from a small nudge to a fuller strategy, keeping the reasoning visible for students, parents, and teachers.
Grade 2 · Add/Subtract on a Number Line
Mission Progress
0/3
Thinking Summary · 1
Mastered[object Object]
[Discovery] Start at 7. Make 6 hops of size 1. Place the END on the number line.
1
Active StepPlace the marker on 13.
2nd Grade Add/Subtract on a Number Line seedling-2 representative practice page for students who need a crawlable, worked entry point into the topic without exposing every near-duplicate long-tail mission.
This seedling · gentle warm-up mission uses a number line to move from the story to a precise add/subtract on a number line idea. Work through the prompts in order: notice the structure first, name the quantities, then check whether the final answer fits the original situation.
Common wrong turn: 7 is where we BEGIN. Hops move us forward.
Common wrong turn: 6 is the COUNT of jumps, not the final position.
Common wrong turn: 20 is the destination, not the count of hops.
In 2nd Grade Add/Subtract on a Number Line, students need to connect the story, the model, and the symbolic answer. The core move here is: 7 + 6 = 13. A useful check is to ask whether the answer avoids this pitfall: Jumping in the wrong direction for subtraction. Plus = right (toward bigger). Minus = left (toward 0). Picture the arrow before the first hop.
Everything you need to know about the Socratic experience.
Start at 7. Make 6 hops of size 1. Place the END on the number line. Hint: Each hop adds +1. From 7, take 6 hops.
Starting from 13, how many MORE hops of size 1 reach 20? If you get stuck, the adaptive hint is: 7 ÷ 1 = 7.
Seedling missions anchor the visual model with small, friendly numbers — ideal as the first attempt at this topic. Within Grade 2 Add/Subtract on a Number Line, expect numbers in the corresponding range.
Jumping in the wrong direction for subtraction. Plus = right (toward bigger). Minus = left (toward 0). Picture the arrow before the first hop.
Add/Subtract within 100 (The number-line view is a second representation of the same arithmetic.) Open /grade-2/addsubwithin100 to start that topic's missions.
Yes. Every mission, handbook page, and topic hub is mapped to a specific CCSS code (visible in the page header). The curriculum follows the CCSS coherence map: Grade 1 number sense → Grade 3 multiplicative thinking → Grade 6 ratio reasoning, with each grade building strictly on the prior year's foundations.
Socratic teaching answers a question with a better question. Instead of "the answer is 12", the system asks "if you had 3 groups of 4, how could you skip-count?" The goal is to externalize the learner's reasoning so they hear themselves think. Every Inquiry AI hint follows this pattern: nudge → reframe → analogy → only then a worked example, in that order.
