Scratch

Scratch is a block-based programming initialy made in 2004, and, it was only targeted at kids to get to learn about coding rather than HTML's, the community get to publish and share their own projects and remix on the platform, some screamers are disguised as kid-friendly to scare children by adding a screamers at the end.

Link
NOTE : the following website contain screamers!
 * scratch.mit.edu