One rule, every next number
Generate named terms by applying an explicit rule.
Explore this lesson →8 practice questions · Optional read aloud · Thinking pad
Let’s understand the idea.
- Read the starting value and the complete rule. The starting value is already term 1.
- Apply the rule to the previous value once for each move. Adding 2 and multiplying by 2 usually give different next values.
- To reach term 6 from term 1, make five moves. Count the moves separately from the term numbers.
- Adding zero or multiplying by one keeps the value unchanged. Multiplying by zero keeps the given first term, then makes every later term zero.
Something to notice
Ask the learner to explain one move in their own words and show why reaching term 6 takes five moves. Try the same starting value with an add-2 rule and a double-it rule, then compare the results. Look for correct use of the previous value and the stated term number. The practice checks generated terms; invite an explanation before assuming the learner understands why they follow the rule.
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.
Let’s try it →Curriculum connection
Grade 4 · 4.OA · US Common Core
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.