A good option is 'The Velveteen Rabbit'. It's a heartwarming story about a toy rabbit that wants to become real. The story is relatively short, around 20 minutes to read aloud. It has a simple yet profound message about love and what it means to be real. You can print it out and make it into a little book for kids.
One popular 20 - minute printable children story is 'The Little Prince'. It's a wonderful tale that takes kids on a journey through different planets and encounters various strange yet interesting characters. The story has beautiful illustrations that can be printed along with the text, and it teaches kids about friendship, loneliness, and the importance of seeing beyond the surface.
There's 'Alice's Adventures in Wonderland'. This classic story is full of whimsical adventures. Alice falls down a rabbit hole into a fantastical world. It has a lot of strange creatures and situations. You can easily find printable versions. It can be read in about 20 minutes and is great for sparking children's imaginations.