Plot the Rocket's Course with Addition Within 20

Starlight Station has lost power and one of the crew is responsible. The course home is plotted one sum at a time: work out eight plus five, then slide the rocket to 13 on a number line that runs past twenty. First graders are supposed to be moving off counting-on and onto making ten, and a number line rewards that — a jump of two to reach ten, then three more, is visibly faster than thirteen single hops. Five course corrections per run, fresh numbers every time.

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What this station asks for

🛰️ Plot the CourseLet's fly to the station! Add each pair, then slide your rocket to the exact number to lock the course. Make a ten if it helps! You work out the answer, then slide the rocket along a number line to set the course. Five tasks, then the flight log goes into the Case File.

Five questions it might ask

Drawn from the same pool the activity uses, so these are the real thing rather than an illustration. The numbers change on every attempt — there is no fixed set to memorize.

Question	Answer
10 + 3 = ?	13
11 + 2 = ?	13
7 + 8 = ?	15
5 + 9 = ?	14
4 + 9 = ?	13

👀 What to watch for

The make-a-ten strategy is the whole point of 1.OA.C.6 and it rarely appears on its own. If a child is still hopping one at a time, ask what number would be easy to land on first. Most first graders say "ten" immediately — they just hadn't thought to use it.

The Common Core standard behind it

Official wording, quoted in full — not our summary of it:

1.OA.C.6	Add and subtract within 20, demonstrating fluency for addition and subtraction within 10. Use strategies such as counting on; making ten; decomposing a number leading to a ten; using the relationship between addition and subtraction; and creating equivalent but easier or known sums.

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Other Grade 1 skills in this case

Subtraction within 201.OA.C.6 Number bonds to 201.OA.C.6 Adding tens within 1001.NBT.C.4

All grades

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