diff --git a/unit2/README.md b/unit2/README.md
index b02f1af..4fc6892 100644
--- a/unit2/README.md
+++ b/unit2/README.md
@@ -44,9 +44,11 @@ Are you new to Discord? Check our **discord 101 to get the best practices** π
3οΈβ£ π **Read An [Introduction to Q-Learning Part 1](https://huggingface.co/blog/deep-rl-q-part1)**.
-4οΈβ£ π **Read An [Introduction to Q-Learning Part 2](https://huggingface.co/blog/deep-rl-q-part2)**.
+4οΈβ£ π Take a piece of paper and **check your knowledge with this series of questions** β π https://github.com/huggingface/deep-rl-class/blob/main/unit2/quiz1.md
-5οΈβ£ π©βπ» Then dive on the hands-on, where **youβll implement our first RL agent from scratch**, a Q-Learning agent, and will train it in two environments:
+5οΈβ£ π **Read An [Introduction to Q-Learning Part 2](https://huggingface.co/blog/deep-rl-q-part2)**.
+
+6οΈβ£ π©βπ» Then dive on the hands-on, where **youβll implement our first RL agent from scratch**, a Q-Learning agent, and will train it in two environments:
1. Frozen Lake v1 βοΈ: where our agent will need toΒ **go from the starting state (S) to the goal state (G)**Β by walking only on frozen tiles (F) and avoiding holes (H).
2. An autonomous taxi π: where the agent will needΒ **to learn to navigate**Β a city toΒ **transport its passengers from point A to point B.**
@@ -58,7 +60,7 @@ The leaderboard π https://huggingface.co/spaces/chrisjay/Deep-Reinforcement-L
You can work directly **with the colab notebook, which allows you not to have to install everything on your machine (and itβs free)**.
-6οΈβ£ The best way to learn **is to try things on your own**. Thatβs why we have a challenges section in the colab where we give you some ideas on how you can go further: using another environment, using another model etc.
+7οΈβ£ The best way to learn **is to try things on your own**. Thatβs why we have a challenges section in the colab where we give you some ideas on how you can go further: using another environment, using another model etc.
## Additional readings π
- [Reinforcement Learning: An Introduction, Richard Sutton and Andrew G. Barto Chapter 5, 6 and 7](http://incompleteideas.net/book/RLbook2020.pdf)
diff --git a/unit2/assets/img/MC-3.jpg b/unit2/assets/img/MC-3.jpg
new file mode 100644
index 0000000..dc74d5b
Binary files /dev/null and b/unit2/assets/img/MC-3.jpg differ
diff --git a/unit2/assets/img/TD-1.jpg b/unit2/assets/img/TD-1.jpg
new file mode 100644
index 0000000..6d59d50
Binary files /dev/null and b/unit2/assets/img/TD-1.jpg differ
diff --git a/unit2/assets/img/bellman4-quiz.jpg b/unit2/assets/img/bellman4-quiz.jpg
new file mode 100644
index 0000000..f2d9585
Binary files /dev/null and b/unit2/assets/img/bellman4-quiz.jpg differ
diff --git a/unit2/assets/img/bellman4.jpg b/unit2/assets/img/bellman4.jpg
new file mode 100644
index 0000000..867bf67
Binary files /dev/null and b/unit2/assets/img/bellman4.jpg differ
diff --git a/unit2/assets/img/mc-ex.jpg b/unit2/assets/img/mc-ex.jpg
new file mode 100644
index 0000000..e7437a2
Binary files /dev/null and b/unit2/assets/img/mc-ex.jpg differ
diff --git a/unit2/assets/img/monte-carlo-approach.jpg b/unit2/assets/img/monte-carlo-approach.jpg
new file mode 100644
index 0000000..09012bf
Binary files /dev/null and b/unit2/assets/img/monte-carlo-approach.jpg differ
diff --git a/unit2/assets/img/summary-learning-mtds.jpg b/unit2/assets/img/summary-learning-mtds.jpg
new file mode 100644
index 0000000..6f55e69
Binary files /dev/null and b/unit2/assets/img/summary-learning-mtds.jpg differ
diff --git a/unit2/assets/img/td-ex.jpg b/unit2/assets/img/td-ex.jpg
new file mode 100644
index 0000000..11d30e7
Binary files /dev/null and b/unit2/assets/img/td-ex.jpg differ
diff --git a/unit2/assets/img/two-approaches.jpg b/unit2/assets/img/two-approaches.jpg
new file mode 100644
index 0000000..b8f6add
Binary files /dev/null and b/unit2/assets/img/two-approaches.jpg differ
diff --git a/unit2/quiz1.md b/unit2/quiz1.md
new file mode 100644
index 0000000..2075759
--- /dev/null
+++ b/unit2/quiz1.md
@@ -0,0 +1,99 @@
+# Knowledge Check βοΈ
+
+The best way to learn and [avoid the illusion of competence](https://fr.coursera.org/lecture/learning-how-to-learn/illusions-of-competence-BuFzf) **is to test yourself.** This will help you to find **where you need to reinforce your knowledge**.
+
+π Take a piece of paper and try to answer by writing, **then check the solutions**.
+
+### Q1: What are the two main approaches to find optimal policy?
+
+
+Solution
+
+The two main approaches are:
+- *Policy-based methods*: **Train the policy directly** to learn which action to take given a state.
+- *Value-based methods* : Train a value function to **learn which state is more valuable and use this value function to take the action that leads to it**.
+
+
+
+π If you don't remember, check π https://huggingface.co/blog/deep-rl-q-part1#what-is-rl-a-short-recap
+
+
+
+
+### Q2: What is the Bellman Equation?
+
+
+Solution
+
+**The Bellman equation is a recursive equation** that works like this: instead of starting for each state from the beginning and calculating the return, we can consider the value of any state as:
+
+$R_{t+1} + ( gamma * V(S_{t+1}))$
+
+The immediate reward + the discounted value of the state that follows
+
+π If you don't remember, check π https://huggingface.co/blog/deep-rl-q-part1#the-bellman-equation-simplify-our-value-estimation
+
+
+
+
+### Q3: Define each part of the Bellman Equation
+
+
+
+
+
+Solution
+
+
+
+π If you don't remember, check π https://huggingface.co/blog/deep-rl-q-part1#the-bellman-equation-simplify-our-value-estimation
+
+
+
+### Q4: What is the difference between Monte Carlo and Temporal Difference learning methods?
+
+
+Solution
+
+There are two types of methods to learn a policy or a value function:
+- With the *Monte Carlo method*, we update the value function **from a complete episode**, and so we use the actual accurate discounted return of this episode.
+- With the *TD Learning method*, we update the value function **from a step, so we replace Gt that we don't have with an estimated return called TD target**.
+
+
+
+π If you don't remember, check π https://huggingface.co/blog/deep-rl-q-part1#monte-carlo-vs-temporal-difference-learning
+
+
+
+### Q5: Define each part of Temporal Difference learning formula
+
+
+
+
+Solution
+
+
+
+
+π If you don't remember, check π https://huggingface.co/blog/deep-rl-q-part1#temporal-difference-learning-learning-at-each-step
+
+
+
+### Q6: Define each part of Monte Carlo learning formula
+
+
+
+
+Solution
+
+
+
+π If you don't remember, check π https://huggingface.co/blog/deep-rl-q-part1#monte-carlo-learning-at-the-end-of-the-episode
+
+
+
+---
+
+Congrats on **finishing this Quiz** π₯³, if you missed some elements, take time to [read again the chapter](https://huggingface.co/blog/deep-rl-q-part1) to reinforce (π) your knowledge.
+
+**Keep Learning, Stay Awesome**