Hi, here are a few riddles that I personally love. Try your best to get the solution without googling the answers.

1. The Riddle of the Old Man
I am sitting next to an old man one day when he tells me that he needs me to help him remember the ages of his 3 grandchildren. Being a smart person (who can any calculation quickly in my head - THIS IS IMPORTANT) I consent. He then proceeds to give me the first thing he remembers:
-The product of the ages of my children is 36
Obviously, I do not know the answer. He sighs and gives me a second clue:
-The sum of the ages of my children is... *he writes a number on a slip of paper*
Even though I can see the paper, I do not know. He scratches his head, then gives me one final clue.
-My eldest son wears glasses.
I know the answer, and tell him the ages of his grandchildren.
The Riddle: What are the ages, and how do you know?

2. The Eye Color Riddle
On a small island, there are 201 people. 100 of them have brown eyes, 100 of them has blue eyes, and one has purple eyes. The one with purple eyes happens to be an all powerful guru who loves holding people hostage. She has imprisoned these 200 people on her island and put an unbreakable charm on them that keeps them from talking. Every day at 12:00 pm, a ferryman arrives. He is also magical, and wants to help as many people as possible escape. And so, he temporarily lifts some of the charm every day at noon, allowing each person to say one word. The trick is, to escape, the person must say the color of their own eyes. If they say anything else, the guru will become angry and kill everyone. Obviously, no one risks it and life wears on. The guru makes sure that these people cannot communicate the color of other people's eyes to them in any way. However, one day, the guru is in a good mood. Being the all powerful deity she is, she can see everyone's eye color. So she gives a helpful clue:
"I see someone with blue eyes."
Every day, the ferryman comes and does his routine questioning. Like with the first riddle, everyone on the island is a supergenius.
The question is: How many people will leave the island, and when will this happen?

Hint: Start by trying the scenario with one blue eyed person and 199 brown eyed people. Two blue eyed people? Three? Four?

3. The Riddle of the Sinful Wizards
One hundred wizards have committed treason and been arrested and put to death. However, their jailer is a nice enough fellow and decides to give the wizards a test. If they pass, they will only have to serve 5 years in prison. The test is as follows:
-On execution day, the wizards will be put in a line. The wizards can see all of the wizards in front of them, but none behind (the last wizard sees all, and the first wizard sees none).
-They will each be given a hat. The hat will either be white or black. They cannot see their own hats. There is no set amount of white or black hats. It could be 50-50, or the hats could be all black or all white or anywhere in between.
-Starting with the last wizard, the executioner will ask each wizard the color of their hat. If they get it right, they get 5 years of prison. If they get it wrong, they die.
-The wizards can plan how they will answer all together on the night before the execution day.
-They must say only "White" or "Black", otherwise everyone will be killed.
-This is not a trick question.
-The wizards all want to be in prison rather than dying.

How can they save the maximum number of wizards?

4. Axe-Happy
4 very smart people are buried in the ground, and an evil villain is about to chop off their heads. Much like the wizards problem (see #3), they can only see the person in front of them. They either have on a red hat or a blue hat. There is a wall infinitely long and wide that is separating the 3rd and 4th people. It cannot be passed. It cannot be seen through.
The evil villain will chop off everyone's heads unless one person can say the color of their own hat. They cannot see their own hats. If one person can correctly name the color, then the day is saved. The villain tells everyone that there are 2 red hats and 2 blue hats.

There are two scenarios in which everyone is saved (there is always a way for everyone to be saved).
The Riddle: Name them both, and explain.
Note: Person 1 is the person that can't see anyone, Person 2 can see Person 1, Person 3 can see both Person 1 and 2, and Person 4 can't see anyone.

5. EXTRA DIFFICULT: Probability... probability...
This riddle is different from the others in that it is not a logic problem, but rather a question of probability. There are no secrets or shortcuts. This is cold, hard math.
A queen has sentenced 3 prisoners to death. She is a merciful queen, and sets up a way to let them all live. But it won't be easy. The queen will put a mark on each of the prisoner's heads. The mark will either be a dot or a dash. There is no set amount of dots and dashes that will be marked. It is completely random. Prisoners can see the other two prisoner's marks, but not their own.
The queen will hand out slips of paper to each prisoner. If they choose, prisoners can guess whether their mark is a dot or dash. All three can guess, or just two, or only one. At least one must guess or they all get executed. In order for them all to be let go, all guesses must be correct. Otherwise, ALL prisoners are executed. The prisoners meet the night before to strategize.
The Riddle: How can the prisoners guess so that the probability of them living is the highest? The probability WILL be greater than 50%. There is no tricks or secret communications. This is solid, honest probability.

Well, there you have it! These riddles are very challenging, so don't feel bad if you can't get them immediately or at all. Keep trying. Take a break. Come back later and try again. You can do it!

Note: Please do not ask obvious questions. These riddles are not tricks. Please forgive me if I didn't put in every little detail. However, feel free to ask if something doesn't make sense.
Examples of Good and Bad Questions:
Sample Riddle: I have 4 apples. How can I distribute them among four friends and still keep one in the basket?
Good Questions: Do I have to give one apple to each friend? (Yes) Can I cut up the apples? (No) I'm stuck, can I have a hint?
Bad Questions: Are the apples oranges in disguise? Is the basket an apple? What do you mean by "apples"?

Happy puzzling! Bonus points if you solve the "good question/bad question" riddle about apples.

Cool riddle.