Cheryl B made a good point about how they do not teach the kids how to read an analog clock, they usually only know how to read a digital clock or watch.. The other thing is many of them do not know how to make change.. We gave our daughter a watch when she was 6 that was an analog..
They cannot count money back.. The cash registers now just tell them the amount.. But if you are working a garage sale or someone id giving you many back, you do not want to be ripped off, so you need to know how to count it back. You can practice this..
Also they do not spend much time on Cursive writing.. You may want to at least have them practice their signatures. And how to read cursive.
Since we do not know what their background is, it is hard to guess why they missed out on these basics. If there was a lot of drama in their households you know that they probably were under a lot of stress and can suffer from memory loss also they could have had their minds on other things rather than school. Being in a survival mode takes a lot of energy for a child.
I look back at my report cards and can totally see that I was a great student until the grade my parents started really having a hard time getting along. My grades completely dropped. Especially the year they separated. Back then Divorce was still considered a bit of a scandal, so it was not discussed outside of the house even with my teachers.
Also families that move around a lot and their children moving from school district to school district can have gaps in their learning. For instance, they taught Roman numerals the first month of our daughters 3rd grade advanced math class, but at that time she was in a regular math class. Once she was switched over, the Roman numerals were then being taught in regular classes and the advanced math had moved on..
And so I was given some work sheets to work with her on this.. If we had moved she would not have met this one math fact and I certainly would not have even thought about it.
So instead of trying to figure out why, you now need to work on things as it comes up.
There are great place mats with the United States on them or you could laminate some maps. At dinner, talk about different states and what the Capital Cities of each state is. Have the kids test you too. When you are going somewhere use a road map. Have this girl plot out a way to go. Teach her how to actually read a map.
Same with the months (get a giant calendar and have the kids add their activities to it. ,For Christmas, give each child their own Calendar, one that matches their interest. the seasons, Roman numerals,
How to balance a check book. Teach them how ti figure out sales tax.
How to follow a recipe. How to keep a budget. Include her int he things you do, like how you stay organized. How to read the electric bill.