What documents, other than ID and passport/birth certificate, are
required for Canadian children (age 13 & 16) visiting the US with only
one parent?
What documents, other than ID and passport/birth certificate, are
required for Canadian children (age 16) visiting the US with a non
parent adult?
Purpose of the visit - vacation, duration of visit - 8 days.

Howdy mrfg,

It appears that it might not be the trip into the US
that you have to prepare for, but rather the return
into Canada.

To find the following entry, you will have to go to
the US Customs & Border Protection website at:
http://www.customs.gov

Then click on the "questions" button on the top
"bar" or go directly to the questions page.
http://help.customs.gov/cgi-bin/customs.cfg/php/enduser/std_alp.php

In the "Search Text (optional)" area, type in: Canada

Click on the resulting entry with the title of:
"Traveling with children, documents, paperwork, identification"

This entry explains what documentation you should be carrying so
as to avoid problems of entry as well as departure.

"Adults traveling out of the U.S. with children under the age of
18 should be aware of the following: because of increasing incidents
of child abductions in disputed custody cases and as possible victims
of child pornography, Customs and INS strongly recommend that unless
the child is accompanied by both parents, the adult have a copy of the
child's birth certificate (preferably notarized) and a short note from
the child's other parent  (or, in the case of a child traveling with
grandparents, uncles or aunts, sisters or brothers, or friends, a note
signed by both parents) stating 'I acknowledge that my wife/husband/etc.
is travelling out of the country with my son/daughter. He/She/They has
my permission to do so.' Customs also suggests that this note be
notarized."

"While Customs or INS may not ask to see this documentation, if they do
ask, and you do not have it, you may be detained until the circumstances
of the child traveling without both parents can be fully assessed. If
there is no second parent with legal claims to the child (deceased, sole
custody, etc.) any other relevant paperwork, such as a court decision,
death certificate, etc., would be useful. Adults  traveling with children
should also be aware that, while the U.S. does not require this
documentation, many other countries do, and failure to produce notarized
permission letters and/or birth certificates could result in travelers
being refused entry. (Canada has very strict requirements in this regard.)"

The America West Airline's Mexico & Canada Travel Advisements web page
has a shorter version of the above that essentially says the same thing.
http://www.americawest.com/services/traveltips/sv_mexico.htm

"Children under 18 years old must provide a valid passport or an original
county or state issued birth certificate or a certified copy of a county
or state issued birth certificate.  A notarized letter of permission to
carry the child outside U.S. boundaries is required from any legal parent
not traveling with the child.  In cases of divorce or death of a parent,
original custody papers verifying full custody to the traveling parent or
an official death certificate eliminates the need for a notarized letter."

You should also read these Canadian Passport Office web page entries
for more details on documentation as well as sample consent letters.

Travelling with children
http://www.ppt.gc.ca/travel_tips/with_child_e.asp

"Documentation to facilitate travel abroad with children.
The following documents may be required to support the
entry of a child to another country:
- Birth certificates showing the names of both parents.
- Any legal documents pertaining to custody.
- A parental consent letter.
- If the child is travelling with one parent, the consent
letter authorizing travel must be signed and dated by
the other parent.
- If the child is travelling without either parent, the
consent letter authorizing travel must be signed and
dated by both parents.
- A death certificate, if one of the parents is deceased."

Children and Travel
http://www.voyage.gc.ca/main/before/faq-en.asp#children

Sample Consent Letter for a Child Travelling with One Parent
http://www.voyage.gc.ca/main/before/consent_ltr1-en.asp

Sample Consent Letter for a Child Travelling without Either Parent
http://www.voyage.gc.ca/main/before/consent_ltr2-en.asp

If you need any clarification, feel free to ask.


Search Strategy:

Went to the US Customs & Border Protection website which I knew
from prior experience.

Google search on keywords: Canada children travel "United States"
://www.google.com/search?q=Canada+children+travel+%22United+States%22

Looking Forward, denco-ga

A comment from personal experience - 

I am a U.S. citizen, a single parent with a 6-year old daughter (also
a U.S. citizen).  My ex's parents (her grandparents) live in Canada,
and we take her there several times a year to visit her grandparents. 
Sometimes one parent goes, sometimes the other.

We have been asked for documentation showing the consent of the
non-travelling parent each and every time (without exception) when
going from the U.S. to Canada, whether travelling by land or air.  We
have supplied her passport and a notarized letter, and that has been
accepted each time.

In making the return trip, from Canada to the U.S., we have never been
asked for any documentation beyond passports.

I don't know if the precise reverse would apply for Canadian citizens,
but it seems to me that if immigration is concerned about possible
child abduction, they would be more concerned about your taking a
child out of his/her country of residence than bringing a child back
in.  So as a Canadian citizen, you may see the reverse pattern.

In the case of a non-parent adult travelling with children, it would
be prudent to bring written, notarized consent from both parents (one
letter ought to be fine if they are married to each other).  The
non-parent adult should also have a separate letter authorizing them
to consent to emergency and urgent medical treatment for the children,
along with information on health conditions, medications, and
allergies.  (The medical consent letter is not necessary for the solo
parent - an individual parent may consent to emergency medical
treatment for a child.  Actually, in the event of an emergency,
consent is implied for a minor child, so the real issue is giving
consent for treatment of urgent situations that do not qualify as
life-threatening emergencies - e.g., broken bones, stitches.)

Two additional comments:

1.  Because the children you are talking about are older, the
immigration officials may take them aside - to a different room - to
ask them privately and individually if they are travelling
voluntarily.  You and the kids should be prepared for this
possibility.
2.  If any of the children are adopted (especially if they are of
different racial heritage so that the immigration officials might
guess they are adopted), I would go belt-and-suspenders on
documentation.  My pediatrician had a difficult time bringing his
adopted Korean daughter back into the United States after a visit to
Canada.  She was adopted 10+ years ago, at the age of three months. 
This trip took place recently, when she was a teenager.  The
immigration officials took her aside privately and asked her where she
was born.  When she responded "Korea," they wanted to see all kinds of
adoption documentation that he did not have with him.  He was able to
bring her back in, but it was a frightening experience for all
concerned.

Also, to raise two questions that you did not ask, have you purchased
international health insurance (if not, you should) and have you
checked into car insurance (if you're driving your own car across the
border)?

International health insurance is a must for anyone travelling
internationally.

On car insurance:  My U.S. car insurance covers me in Canada, but not
unless I request and get a special form showing that it does.  If by
chance you are driving your own car, you might want to check on this
point with your Canadian insurance carrier.

Research Strategy:  life experience


Here's to all parties having an enjoyable and safe trip!