List of Skills by Age

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1-2 Months

Although research exists for documenting number sense in the first year of life. These are laboratory studies that cannot be replicated in home visits or centers. For this reason, skills the first year of life have been omitted.

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2-4 Months

Although research exists for documenting number sense in the first year of life. These are laboratory studies that cannot be replicated in home visits or centers. For this reason, skills the first year of life have been omitted.

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4-6 Months

Although research exists for documenting number sense in the first year of life. These are laboratory studies that cannot be replicated in home visits or centers. For this reason, skills the first year of life have been omitted.

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6-8 Months

Although research exists for documenting number sense in the first year of life. These are laboratory studies that cannot be replicated in home visits or centers. For this reason, skills the first year of life have been omitted.

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8-10 Months

Although research exists for documenting number sense in the first year of life. These are laboratory studies that cannot be replicated in home visits or centers. For this reason, skills the first year of life have been omitted.

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10-12 Months

Although research exists for documenting number sense in the first year of life. These are laboratory studies that cannot be replicated in home visits or centers. For this reason, skills the first year of life have been omitted.

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12-15 Months

Keeps track of quantities up to 3 (when they are moved out of sight)

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15-18 Months

No observable skills

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18-21 Months

Knows “one more”

Looks at two sets of items with a large difference in amount and knows which has more

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21-24 Months

Instantly recognizes amounts of 2 or 3 without counting (two shoes)

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24-27 Months

Gives one out of many items

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27-30 Months

Identifies first in a sequence and sometimes the second

Identifies more than 3 as “many”

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30-33 Months

Instantly tells how many with groups of 1-3 items

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33-36 Months

Visually identifies “same” or “more” (may be wrong)

Understands concept of “all” or “none” relating to number of objects

Examines a small group of objects and knows which has more if there is a big discrepancy

Starts to recognize written numbers

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36-42 Months

Compares amounts in two groups up to six items by matching with one-to-one correspondence (gives each toy animal a block for hay)

May be confused by amount if one set of items is physically larger

Recognizes several written numbers

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42-48 Months

Instantly recognizes amount up to four and names the amount

Compares amounts in each of two sets by counting (up to 5 items)

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48-54 Months

Understands “same number as”

Recognizes the written numbers 1-9

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54-60 Months

Uses counting to compare amounts in sets even if items are different sizes

Visually structures and verbally labels two visual amounts and identifies the total amount (up to 10)

Keeps track of number counted even when not in a structured arrangement

Writes and draws to represent 1 to 10 and 20 and 30