I have an awesome friend, Kenji, who is 9 years old and loves his iPad. He loves to build things with Legos and is a huge Minecraft fan.

I spent a Sunday teaching him 3D modeling and I was shocked when it only took him a couple of hours to learn it. (All that time in Minecraft actually paid off.) I had a well thought out plan to accomplish this (his mom certainly helped plant the seed) and I want to share what worked for us.

At the end of the day, 3D modeling skills allowed him to design and 3D print something he thought would be cool. In this case, he ended up making a custom Monopoly skyscraper so he could change the rules of the game, charge a ton of rent, bankrupt his family, and win the game :)

Here's what you need and it's free:

Autodesk 123D Design iPad App

Autodesk 123D Design Desktop App (Mac or Windows)

Step 1: 3 Things to 3D Model

3 things you need to know to 3D model:

1. Rotate, zoom, & pan

2. Snapping parts together

3. Extruding

Those are the basics. Play around with those tools a little bit and you are on your way to creating and inspiring another generation.

Step 2: The Plan

123D Design iPad app is an excellent way to introduce the concept of 3D navigation - you move and twirl things with your fingers.

Once he was familiar with the iPad app, I introduced a more powerful desktop version of 123D Design that required a 3-button mouse. At this point, I was really proud to work for Autodesk: we have an easy-to-use iPad app and a desktop version with similar interfaces so people can easily learn more complex 3D modeling software packages. So cool. AND IT WORKED.

Step 3: IPad Rotate, Zoom, & Pan

Use hand gestures to manipulate the model. This is why it's really great to start 3D modeling with the iPad - manipulating the model with your hands helps develop spacial orientation.

Step 4: IPad 3D Navigation - Rotate, Zoom, & Pan With a Cube

In the primitives menu on the right, select a cube. Notice the instructions at the top of the screen - "tap or drag to place a part."

Use the hand gestures to rotate, zoom, & pan the cube.

Step 5: IPad Snapping Parts Together

Place another cube on the screen. Open the Adjust menu and select Snap. Follow the instructions at the top of the screen - "Tap a face, then tap another object's face to snap them together."

This connects or snaps two objects together.

Step 6: IPad Extruding

Select the Reshape menu and select the third icon down. Read the instructions at the top of the screen, "Tap a face, then drag to pull in or out."

Tap the right face and drag! This pulled (or extruded) the face of the bottom cube.

Step 7: Summary

Those are the three fundamental concepts of 3D modeling:

1. Rotate, zoom, and pan

2. Snapping two things together

3. Extruding

With those 3 tools you can do almost anything.

Keep exploring the app and trying new tools. When you start a tool, remember to read the instructions at the top of the screen. Take your time and be precise.

Step 8: Desktop Version 123D Design

Let's take 3D design to the next level by increasing the complexity. Download and install the 123D Design desktop app.

Step 9: Desktop 3D Navigation - Rotate, Zoom, & Pan

A 3-button mouse is an essential tool for every 3D designer. Here's how you use it:

Rotate - right mouse button click and hold

Zoom - scroll middle mouse button

Pan - press middle mouse button and move mouse

Practice this on two boxes.

Step 10: Desktop Snapping Parts Together

The snap tool has the same icon as the iPad app! Whoo hoo. Select the snap tool and follow the instructions at the tip of your mouse.

Step 11: Desktop Extruding

In the Construct menu, you'll find the familiar Extrude icon. Select the extrude icon, move your mouse to the graphics window, and follow the instructions - "Select a 2D shape or face of a solid to extrude."