Mental maths & known facts

Known facts: 4 and 5

Build reliable recall for sums starting with 4 or 5.

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20 practice questions · Optional read aloud · Thinking pad

Let’s understand the idea.

  1. Practice every sum of 4 or 5 with a one-digit number. Your place is saved when you take a break.
  2. Try recalling a fact. If it does not come yet, use a connection you understand and ask for help.
  3. When you revisit, notice which facts you now know and which still need a strategy. There is no race.

Something to notice

Ask which facts the learner recalls and which they derive, and revisit them over time in varied contexts. There is no speed score. A correct untimed answer does not prove automatic recall or fluency; the app records practice and support, not a claim that this standard is mastered.

Try it. Change it. Explain it.

Open the lesson to use its pictures and controls. In How it works, connect the picture to the idea. In Play & discover, change the quantities and notice what stays the same. In Your turn, answer questions and use the explanation to check your reasoning.

You can ask for help, draw on the thinking pad, or listen to the question and answer options. Progress distinguishes independent work from work completed with help.

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Curriculum connection

Grade 2 · 2.OA · US Common Core

2.OA.B.2

This lesson is mapped to these standards. A completed activity is practice evidence, not a claim of mastery. Content is checked against the linked official standards and its mathematical models are tested.

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