Elementary CS: Grades K-2

Teaching computer science to five, six, and seven year olds is mostly about patterns, following directions, and learning that being precise with instructions matters. You will not be writing code on screens (usually), and that is fine. The concepts that matter at this stage (sequencing, decomposition, simple data sorting) all work beautifully with hands-on, unplugged activities. This page gives you a practical lesson flow structure, materials guidance, warm-up ideas, and the differentiation tips that keep a mixed-ability K-2 room moving.

Suggested Lesson Flow

This structure works for most K-2 CS sessions. Adjust timing based on your students and the specific activity.

Warm-Up (5 minutes)

Start with a quick, whole-group activity that activates the concept for the day. Examples:

• Pattern clap: Clap a pattern (clap-clap-stomp, clap-clap-stomp) and ask students to continue it or create their own.
• Simon Says (precise version): Give instructions that students must follow exactly. If you say "touch your nose" and someone touches their ear, talk about why precision matters.
• Sort the day: Show three images from the school day (arrival, lunch, dismissal) and ask students to put them in order.

Mini-Lesson (8 to 10 minutes)

Introduce or revisit one concept. Keep it to one idea per session. Use physical demonstrations: walk through an "algorithm" for sharpening a pencil (step 1: pick up the pencil, step 2: walk to the sharpener...) and show what happens if you skip a step or put them out of order.

Practice (10 to 15 minutes)

Students work individually or in pairs on an activity that uses the concept. This is the core of the session. Walk the room, ask questions ("What happens next?" "How did you know?"), and note who is struggling or racing ahead.

Reflection (3 to 5 minutes)

Bring the group back together. Ask two or three students to share what they did. Ask the group: "What was hard?" and "What would you do differently?" Even kindergartners can answer these if you keep the language simple.

Differentiation Tips

• For students who finish early: Ask them to create a more complex version of the activity (a longer pattern, a more detailed set of instructions) or have them help a neighbor. Helping is a real CS skill (pair programming starts here).
• For students who need more support: Reduce the number of steps. If the class is making four-step sequences, let these students start with two. Use physical manipulatives rather than paper-based tasks when possible.
• For students who need a challenge: Introduce the idea of "bugs." After they complete their instructions, ask: "What if step 2 was wrong? What would happen?" This is early debugging without calling it that.

Materials List

Common Snags and How to Handle Them

• "I do not get it." Usually means the instructions were too abstract. Switch to a physical demonstration with the student.
• Students skipping steps. Normal at this age. Reinforce the value of precision by showing what happens when a step is missing. Make it funny, not punitive.
• Uneven pairs. If one partner dominates, use a turn-taking rule: one person gives instructions for 2 minutes, then they swap.
• Running out of time. It happens. Prioritize the warm-up and practice. The mini-lesson and reflection can be shortened if needed.

What Comes Next

After K-2, students move into the 3-5 grade band where the concepts shift from unplugged pattern work to loops, conditionals, and simple variables. The skills built here (sequencing, precision, decomposition) are the foundation for everything that follows.