user23371: This what I have learned :
digital inputs and outputs 

Analog inputs and outputs

Line follower ir sensor 

Pir sensor 

Ultransonic sensor

Ir transmitter and reciever 

Lcd 

Key pad

Dc motor 

Stepper motor

Servo motor

Interrupts 

Timers 

Watchdogs 

 Arduino with raspberry pi 

This topics a made with it some projects so the question is what is next to learn about arduino ? What should be my next steps ?? 

user16417: I would get myself familiar with low power, sleeping modes, running on batteries.
Also connect others devices using SPI and I2C to familiarize yourself.
Finally give a go on different communication methods... over serial, ethernet, wireless, can bus, etc. No much point in having stand-alone projects that are isolated or always connected to an USB port. IMO the fun begins when your projects start to talk to each other and to the Internet.
Cheers 

user8033: Combine
I see a lot of loose "projects", but try to fit (as much as possible) into one single project. Make a line following robot, that balances, has WiFi communication and a display.
Putting all the different parts together may create whole new problems/difficulties.
Stop using Arduino?
Find another IDE, so it's easier to manage a lot more code.
Learn how to set up a toolchain/compiler.
Try programming an ATMega328P without Arduino.
Why? Because it'll learn you how to other devices work, if you're comfortable programming an AVR without Arduino, it's just a little step to using PIC microcontrollers.
Hardware
Design yourself a PCB specific for the project you want to do.
Work on "Professional skills"
Try to make some actual designs, requirement analyses and make a report on the project. This way you can practice for school/future jobs' professional skills.
So what project should you do?
Something you would really like to do.
It's as simple as that.
Something of which you think is going to be a challenge (but not too challenging).

user20245: You say you have learned these things but were you using a motor shield for the DC motor?  How's about building your own H-bridge. And how many types of stepping motors do you now know how to control?  What about micro stepping? And what about graphical LCDs. Do you know how to make custom characters?
As your list is hardware-centric, I would next task you to learn how to write in C++ and create a library for others to use.  Learn what it means to abstract the hardware down to a few simple function calls.  How to create a class which contains an Arduino library for, say, the graphical features of a particular LCD.

23371: <p>This what I have learned :</p>

<pre><code>digital inputs and outputs 

Analog inputs and outputs

Line follower ir sensor 

Pir sensor 

Ultransonic sensor

Ir transmitter and reciever 

Lcd 

Key pad

Dc motor 

Stepper motor

Servo motor

Interrupts 

Timers 

Watchdogs 

 Arduino with raspberry pi 
</code></pre>

<p>This topics a made with it some projects so the question is what is next to learn about arduino ? What should be my next steps ?? </p>
 16417: <p>I would get myself familiar with low power, sleeping modes, running on batteries.</p>

<p>Also connect others devices using SPI and I2C to familiarize yourself.</p>

<p>Finally give a go on different communication methods... over serial, ethernet, wireless, can bus, etc. No much point in having stand-alone projects that are isolated or always connected to an USB port. IMO the fun begins when your projects start to talk to each other and to the Internet.</p>

<p>Cheers </p>
 8033: <p><strong>Combine</strong></p>

<p>I see a lot of loose "projects", but try to fit (as much as possible) into one single project. Make a line following robot, that balances, has WiFi communication and a display.</p>

<p>Putting all the different parts together may create whole new problems/difficulties.</p>

<p><strong>Stop using Arduino?</strong></p>

<p>Find another IDE, so it's easier to manage a lot more code.
Learn how to set up a toolchain/compiler.</p>

<p>Try programming an ATMega328P without Arduino.</p>

<p><em>Why?</em> Because it'll learn you how to other devices work, if you're comfortable programming an AVR without Arduino, it's just a little step to using PIC microcontrollers.</p>

<p><strong>Hardware</strong></p>

<p>Design yourself a PCB specific for the project you want to do.</p>

<p><strong>Work on "Professional skills"</strong></p>

<p>Try to make some actual designs, requirement analyses and make a report on the project. This way you can practice for school/future jobs' professional skills.</p>

<p><strong>So what project should you do?</strong></p>

<p>Something you would really like to do.
It's as simple as that.
Something of which you think is going to be a challenge (but not too challenging).</p>
 20245: <p>You say you have learned these things but were you using a motor shield for the DC motor?  How's about building your own H-bridge. And how many types of stepping motors do you now know how to control?  What about micro stepping? And what about graphical LCDs. Do you know how to make custom characters?</p>

<p>As your list is hardware-centric, I would next task you to learn how to write in C++ and create a library for others to use.  Learn what it means to abstract the hardware down to a few simple function calls.  How to create a class which contains an Arduino library for, say, the graphical features of a particular LCD.</p>
