Popcorn

Checkpoint challenge. Language: Python.

Prediction: stars = 12, checkpoint_stars = 8. stars starts at 8, and checkpoint_stars = stars copies the value 8 at that moment. Then stars is reassigned to 8 + 4 = 12, but nothing reassigns checkpoint_stars.

Code Runner Challenge

UESL 3.1 Popcorn - Keep the checkpoint

View IPYNB Source 
# CODE_RUNNER: UESL 3.1 Popcorn - Keep the checkpoint
stars = 8
checkpoint_stars = stars    # copies the value 8, not a link to stars
stars = stars + 4           # right side first: 8 + 4 = 12, then assign to stars
print(stars)
print(checkpoint_stars)
Lines: 1 Characters: 0
Output
Click "Run" in code control panel to see output ...

Actual output: 12, then 8. Matches the prediction.

Why they differ: a checkpoint stores the value at the moment of assignment. Reassigning stars replaces only the value of stars. checkpoint_stars keeps 8 until something assigns to it again.

MCQ

**MCQ 3.1: 4/4 answers: B,A,C,B**
  1. B (string). "007" is in quotes, and text keeps the leading zeros. As an integer it would become 7.
  2. A (8). checkpoint ← stars copied 8. Setting stars ← 12 later doesn’t change checkpoint.
  3. C (←). In AP pseudocode the arrow assigns. = tests equality in AP pseudocode (it assigns in Python), and == is Python’s equality test.
  4. B (when reassigned/recalculated). A total is a stored result, not a live formula. Changing a level’s stars or displaying the total doesn’t update it. Only a new assignment does.

Homework

Build your UESL star counter. Language: Python.

game_name is a string, reduced_motion is a Boolean (on/off setting), and each level’s stars is an integer count. Level two gets a 5-star bonus, then the stored total is printed before and after recalculating.

Prediction: Star Sprint, True, 40, then 40 (the stored total doesn’t change by itself), then 45 after recalculating.

Code Runner Challenge

UESL 3.1 Homework - Star Sprint star counter (bonus 5)

View IPYNB Source 
# CODE_RUNNER: UESL 3.1 Homework - Star Sprint star counter (bonus 5)
game_name = "Star Sprint"
reduced_motion = True
level_one_stars = 12
level_two_stars = 18
level_three_stars = 10

total_stars = level_one_stars + level_two_stars + level_three_stars
print(game_name)
print(reduced_motion)
print(total_stars)

# add the bonus to level two
bonus = 5
level_two_stars = level_two_stars + bonus

# the stored total was calculated before the bonus, so it is still 40
print(total_stars)

# recalculate from the levels to pick up the bonus
total_stars = level_one_stars + level_two_stars + level_three_stars
print(total_stars)
Lines: 1 Characters: 0
Output
Click "Run" in code control panel to see output ...

Actual output: Star Sprint, True, 40, 40, 45. Matches the prediction.

Total Predicted Actual
Original 40 40
Stored (after bonus, before recalculating) 40 40
Recalculated 45 45

Tests

Language: Python. Each test starts from fresh values.

Test 1: Bonus 5 is the homework cell above: 40 → 40 → 45.

Test 2: Restart with bonus 0

Prediction: 40, 40, 40. Level two stays at 18, so recalculating gives the same total.

Code Runner Challenge

UESL 3.1 Test - restart with bonus 0

View IPYNB Source 
# CODE_RUNNER: UESL 3.1 Test - restart with bonus 0
game_name = "Star Sprint"
reduced_motion = True
level_one_stars = 12
level_two_stars = 18
level_three_stars = 10

total_stars = level_one_stars + level_two_stars + level_three_stars
print(total_stars)

bonus = 0
level_two_stars = level_two_stars + bonus
print(total_stars)

total_stars = level_one_stars + level_two_stars + level_three_stars
print(total_stars)
Lines: 1 Characters: 0
Output
Click "Run" in code control panel to see output ...

Actual output: 40, 40, 40.

Test Bonus Expected Actual Pass
Main 5 40, 40, 45 40, 40, 45 Yes
Restart 0 40, 40, 40 40, 40, 40 Yes

With bonus 5, the middle line shows the stored total lagging behind the new level-two value until it’s recalculated. With bonus 0 nothing changes, so all three match. Assignment vs. comparison: total_stars = ... assigns a new value; total_stars == 45 would only check it and change nothing.

Design Thinking

Step Notes
Need Some players need to play without distracting motion.
Goal Make motion adjustable so more players can enjoy the game, and keep the star count correct after bonuses.
Considered A settings toggle stored as a Boolean (reduced_motion = True / False), versus a text setting like "on" / "off" that could be misspelled. Went with the Boolean.
Prototype This notebook stores the player’s choice in reduced_motion and tracks stars per level.
Test / revision My first version computed updated_total = stored_total + 5, so level two’s stars never actually changed. I revised it to add the bonus to level_two_stars and recalculate the total from the levels, then reran both bonus cases.

Reduced motion should be the player’s choice because comfort and accessibility are different for everyone. Motion that’s fine for one player can make another feel sick or lose focus.