By Age One

• Recognizes name
• Says 2-3 words besides "mama" and "dada"
• Imitates familiar words
• Understands simple instructions
• Recognizes words as symbols for objects: Car - points to garage, cat - meows

Between One and Two

• Understands "no"
• Uses 10 to 20 words, including names
• Combines two words such as "daddy bye-bye"
• Waves good-bye and plays pat-a-cake
• Makes the "sounds" of familiar animals
• Gives a toy when asked
• Uses words such as "more" to make wants known
• Points to his or her toes, eyes, and nose
• Brings object from another room when asked

Between Two and Three

• Identifies body parts
• Carries on 'conversation' with self and dolls
• Asks "what's that?" And "where's my...?"
• Uses 2-word negative phrases such as "no want".
• Forms some plurals by adding "s"; book, books
• Has a 450 word vocabulary
• Gives first name, holds up fingers to tell age
• Combines nouns and verbs "mommy go"
• Understands simple time concepts: "last night", "tomorrow"
• Refers to self as "me" rather than by name
• Tries to get adult attention: "watch me"
• Likes to hear same story repeated
• May say "no" when means "yes"
• Talks to other children as well as adults
• Solves problems by talking instead of hitting or crying
• Answers "where" questions
• Names common pictures and things
• Uses short sentences like "me want more" or "me want cookie"
• Matches 3-4 colors, knows big and little

Between Three and Four

• Can tell a story
• Has a sentence length of 4-5 words
• Has a vocabulary of nearly 1000 words
• Names at least one color
• Understands "yesterday," "summer", "lunch time", "tonight", "little-big"
• Begins to obey requests like "put the block under the chair"
• Knows his or her last name, name of street on which he/she lives and several nursery rhymes

Between Four and Five

• Has sentence length of 4-5 words
• Uses past tense correctly
• Has a vocabulary of nearly 1500 words
• Points to colors red, blue, yellow and green
• Identifies triangles, circles and squares
• Understands "In the morning" , "next", "noontime"
• Can speak of imaginary conditions such as "I hope"
• Asks many questions, asks "who?" And "why?"

Between Five and Six

• Has a sentence length of 5-6 words
• Has a vocabulary of around 2000 words
• Defines objects by their use (you eat with a fork) and can tell what objects are made of
• Knows spatial relations like "on top", "behind", "far" and "near"
• Knows her address
• Identifies a penny, nickel and dime
• Knows common opposites like "big/little"
• Understands "same" and "different"
• Counts ten objects
• Asks questions for information
• Distinguished left and right hand in herself
• Uses all types of sentences, for example "let's go to the store after we eat"

Source: LDOnline, Learning Disabilities Association of America Fact Sheet, 1999