I’m tall when I’m young, and I’m short when I’m old. What am I?

I am under you when I am whole.
I shift above you if you remove the first letter.
I come all around you if you remove the second as well.

Can you tell me who I am?

Find the next number in the series?
2, 12, 36, 80, 150, 252, 392, _ ?

Christina has four daughters, and each of her daughters has a brother. How many children does Christina have?

The teacher told the student that if he told a lie then he will be expelled from school and if he told the truth then he still is expelled from school.

What can a student say to prevent his being expelled from school?

I came first on earth but second on the heaven.
I also came twice in a week but found just once in a year.
I stay away from months but you can find me in February.

What am I?

Railroad Crossing, look out for the cars. Can you spell that, without any R's ?

John was going on a jungle trip. He asked his wife to pack something to eat, something to drink and something to burn if he feels cold in the jungle. When John opens the backpack he found just one thing in the bag. What was it?

You may enter, but you may not come in. I have space, but no room. I have keys, but open no lock. What am I?

John can place six large boxes or nine small boxes into a carton.

Can you find out in how many cartons can he place sixty-six boxes in total?