To make sure that children receive their vaccines on time, the CDC, American Academy of Pediatrics and Academy of Family Physicians have established a recommended schedule of shots.

At birth
Hep B

2 Months
Hep B (second dose should be given between 2 months and 4 months)
Rotavirus
DTaP
Hib
PCV
Polio

4 Months
Rotavirus (second dose)
DTaP (second dose)
Hib (second dose)
PCV (second dose)
Polio (second dose)

6 Months
Hep B (third dose should be given between 6 months and 18 months)
Rotavirus (third dose)
DTaP (third dose)
PCV (third dose)
Polio (third dose should be given between 6 months and 18 months)
Influenza (and given every year until at least 19 years old)

1 year
Hib (third dose should be given between 12 months and 15 months)
PCV (fourth dose should be given between 12 months and 15 months)
MMR (first dose should be given between 12 months and 15 months)
Varicella (first dose should be given between 12 months and 15 months)
Hep A (starting at 1 year, two doses are needed at least 6 months apart)

15 months
DTaP (fourth dose should be given between 15 and 18 months, as long as it is six months after the third dose)

4 to 6 years
DTaP (fifth dose)
Polio (fourth dose)
MMR (second dose)
Varicella (second dose)

11 to 12 years
HPV (for girls, three doses should be given over the span of six months)