Based on Sesame Street, the long-running PBS children's television show, Sesame Street 123 for the NES stars Bert's best friend and roommate Ernie, and the lovable blue muppet Grover. "Ernie's Magic Shapes" consists of six different magic show-themed games that help teach children colors, shapes, and pattern recognition.

Children are asked to match simple shapes and colors and to choose specific shapes to form things like rocket ships, wheelbarrows, and birds. Astro-Grover features five different outer space-themed games that help teach children simple arithmetic. Children can add, count, and subtract little green aliens called "Zips." When a child gets an answer wrong, he or she is gently informed and allowed to try again.