Put down your phone! This weekend, create your own STEM robot. Does another lazy weekend sound disappointing? Maybe you want a hands-on project that feels truly satisfying. Many people think building robots is hard and costly. In fact, it's easier and quite cheap.
This guide changes that by walking you through 5 easy, budget-friendly STEM robot projects for your weekend. They integrate basic principles in a fun way and become your introduction to robotics. If you're looking for stem robotics kits, consider the ELEGOO UNO Project Super Starter Kit, which comes with everything you need and high praise for its simple setup. Ready to start?
Preliminary knowledge: Before you start: What do you need to know?
This project is perfect for students, beginners, or a parent and child to do together. It is designed for builders aged ten and older. Younger kids will need a grown-up's help. We'll start with the basics, so you can jump right in with no previous skills.
Basic Tool List
Due to Arduino Uno's ease of use and excellent support, it is a great option for beginners. A breadboard, a 9V battery or USB power source, Dupont jumper wires, and a basic set of screwdrivers are also needed. These parts on sites like Amazon, retail for less than $20.
A full kit like the Arduino Starter Kit is a smart option. It comes with the Uno, wires, sensors, and a guidebook. It’s perfect for STEM robotics with kids. People like that it has everything for several projects, so you won't need to buy more parts.
Common Core Components
Most projects here use motors or servo motors for movement, a motor driver board like the L298N to control speed and direction, and sensors for interaction (we'll detail these per project). Servos, such as the SG90, are great for precise angles, while DC motors handle basic driving.
Programming Basics
No prior coding skills? That's okay. You can use visual tools like Arduino's block editor or write simple C++ code. Begin with core concepts such as "if-else" for choices and loops for repeating tasks. Arduino's tutorials walk you through it: grab the free IDE, connect your board, and upload code fast. For children, mBlock offers drag-and-drop coding that feels like play.
You're set with these foundations. In addition to making building more accessible, these tools aid in selecting the best stem robotics kits. The Makeblock mBot kit, for example, integrates everything with ease and receives high marks for its educational value in 2025 reviews.
Project 1: 🤖 Ultrasonic obstacle avoidance car - the "eyes" of the robot
First on our list is the ultrasonic obstacle avoidance car. This popular STEM project lets you build a smart vehicle that navigates around objects on its own. You will learn about ultrasonic sensors that measure distance using sound. It’s like giving a robot the ability to see with sound, similar to how bats navigate.
Core Science
Ultrasonic sensors emit high-frequency sound pulses. They determine distance by timing how long the echo takes to return. This involves physics, like wave behavior, and engineering, by applying them to a system. It's a perfect introduction to robotics for STEM learning.
Key Components
You'll need an Arduino Uno as the brain, an L298N motor driver board for controlling the wheels, and an HC-SR04 ultrasonic sensor for "seeing" ahead. Add a chassis kit with two DC motors and wheels—these are often bundled in cheap stem robotics kits like the ELEGOO Smart Robot Car Kit, which gets excellent reviews for its durability and ease. Total cost: around $15-25 if sourcing individually.
Step Overview
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Mechanical Assembly: To fasten motors to chassis, use screws. With double-sided tape, attach Arduino and driver board to the top. For a quick fix, use hot glue attach the ultrasonic sensor to the front.
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Circuit Connection: Connect your motors to the L298N driver. Link IN1 to IN4 on the L298N to Arduino pins 5 through 8. For HC-SR04, attach Trig to pin 9 and Echo to pin 10. Provide power with 5V and a ground connection. Use a breadboard for clean wiring.
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Programming Implementation: Use Arduino IDE, create a basic sketch. Use if-else statements: If the measured distance is under 20cm, reverse or turn. Otherwise, proceed forward. Example: if (distance < 20) { turnLeft(); } else { forward(); }. Upload and test on a flat surface.
Once built, watch your car navigate a room autonomously. For extended learning, dive into sensory input and decision algorithms—add more sensors for better avoidance. This project builds foundational skills in feedback loops, common in advanced robotics.
You can also refer tutorials like Science Buddies for detailed diagrams. If buying a kit, the OSOYOO Robot Car Kit best for beginners, with step-by-step videos included.
Project 2: 🎨 Simple drawing robot - a combination of coding and art
Next up is a creative twist: a simple drawing robot that sketches shapes on paper. The aim is to blend coding with art, turning abstract math into tangible drawings. This project highlights motor control and coordinate systems, showing how engineering meets creativity in STEM robotics. For guidance, YouTube has awesome tutorials like "Weekend Projects - TRS Drawbot."
Core Science
Servo motors provide precise angular control, mapping movements to an X-Y plane like a plotter. It involves math for coordinates and engineering for kinematics—how parts move together.
Key Components
Two SG90 servo motors for axes, an Arduino Uno, and a pen or marker. Use cardboard or popsicle sticks for the arm. Kits like the Thames & Kosmos Robotics Smart Machines include similar parts and are praised for sparking imagination in 2025 reviews.
Step Overview
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Mechanical Assembly: Construct a two-axis arm. Mount one servo on a sturdy base. Connect a second servo to it using lightweight arms. Fix a pen holder to the end. A light build improves movement precision.
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Programming Implementation: Connect servos to Arduino pins 9 and 10. Code loops to move in patterns:
for (int x = 0; x < 180; x += 5) { servoX.write(x); delay(50); }. Draw circles or stars by coordinating angles.
Extend by exploring kinematics—adjust code for complex shapes—and programming loops for repetition. This is great for STEM robots for kids, teaching iteration visually.
Project 3: 💡 Ray tracing robot - dancing with light source
This light-seeking robot, a popular "solar buggy" project, offers a engaging introduction to bionics in STEM. The aim is to construct a car that autonomously finds and travels to the brightest light, much like a sunflower turns toward the sun or a moth is guided by a lamp. This ties into science (light detection) and technology (control systems), making it ideal for robots for STEM education.
Core Science
Photoresistors, or LDRs, change resistance based on light exposure—the brighter the light, the lower the resistance. By using two LDRs, the robot detects differences (differentials) and adjusts motors accordingly. This introduces concepts like phototaxis in biology and feedback loops in engineering, where the system constantly corrects its path.
Key Components
You'll need two photoresistors (LDRs) for sensing, an Arduino Uno as the controller, and an L298N motor driver board for the wheels. Include a chassis with DC motors, jumper wires, and a breadboard. For a ready-made option, the Sphero Indi kit offers similar sensor-based play and ranks highly in 2025 reviews for engagement in STEM robots for kids. Total cost: about $10-20. If buying individually, grab LDRs from electronics stores—they're cheap and versatile.
Step Overview
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Sensor Installation: Each of the two LDRs attach a 10kΩ resistor, tie the output wire to a Arduino analog pin (like A0 or A1).
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Circuit Connection: Attach motors to L298N driver. A 9V battery that shares ground with the Arduino powers the driver. This setup allows variable speed based on light differences.
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Programming Implementation: In the Arduino IDE, read analog values from the LDRs. Compare intensities: If left > right, slow the left motor or speed up the right to turn toward light. Sample code:
Discuss feedback systems and bionics for deeper learning. Tutorials on Learn Robotics provide clear steps.
Project 4: 📱 Bluetooth/App controlled car - use your mobile phone to remotely control your creation
Upgrade your STEM robotics project by building a Bluetooth-controlled car. Guide your vehicle wirelessly using a smartphone. This project teaches you to create a car that responds instantly to your phone's commands. You will learn about wireless technology and human-computer interaction principles.
Core Science
Bluetooth modules such as the HC-05 let your phone talk to the Arduino. They send messages that the Arduino reads. You will learn to interpret these commands and tell the motors what to do. This process teaches core concepts in IoT and remote control systems.
Key Components
Arduino Uno, HC-05 Bluetooth module, L298N motor driver, chassis with DC motors, and jumper wires. Power with a 9V battery. The WhalesBot E7 Pro kit is a great starter with Bluetooth features, lauded in 2025 reviews for ease. Cost: $15-30. Use free apps like "Bluetooth Serial Controller" or build one with MIT App Inventor.
Step Overview
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Hardware Connection: Set up the Arduino and put the chassis together. To protect against 5V, connect HC-05 to wire L298N and a voltage divider (1kΩ/2kΩ resistors).
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App Settings: Download a free Bluetooth app (e.g., "Arduino Bluetooth RC Car" on Google Play). Pair your phone with HC-05 (default password 1234). Configure buttons to send chars like 'F' for forward.
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Programming Implementation: Code to receive and act on commands.
Project 5: 🌱 DIY manipulator/gripper - Exploring the secrets of bionics
Make your own DIY gripper with basic mechanical concepts and common items. Take ideas from the movements of human hands or animal claws. The goal is to create a working arm that requires only one servo motor to open and close.
Core Science
Levers amplify force, while strings act as tendons pulled by the servo. This simulates bionic design, where biology inspires tech—like how bird beaks or insect mandibles work.
Key Components
One SG90 servo motor, popsicle sticks or straws for fingers, string for tendons, cardboard for base, hot glue, tape, and a push button or potentiometer for control. The ACEBOTT kit is excellent for grippers, with high ratings for beginners. Cost: under $10 using household items.
Step Overview
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Mechanical Assembly: Cut popsicle sticks to 2/3 length, glue at 20° angles for claws. Tape pairs for strength. Cut cardboard rectangle (length of claw x 4.5cm), glue claws to edges, form half-box base. For top: Bend square cardboard 90°, notch center, insert sticks, glue.
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Connection Control: Glue servo horizontally to top base. Connect servo: Brown to GND, red to 5V, orange to pin 3. Use button: One leg to pin 7 via 10kΩ resistor, other to GND. String ties to servo horn, threads through claws as tendons.
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Programming Implementation: Code for button-triggered grip:
Summary: You have successfully completed it! What’s next?
Congratulations on tackling these projects! You've mastered electronics, programming, and mechanics through hands-on STEM robotics. Next, try combining them or exploring advanced kits. Drop questions in the comments—let's build together!
