Update DESIGN.md

DESIGN.md

@@ -70,180 +70,6 @@ The overarching goal of Hedy is to successively add syntactic complexity to a Py
     later have more motivation to learn the details of the syntax.
 
 
-Levels
-------
-
-In its current form, Hedy consists of 22 different levels. The levels loosely
-follow the lesson series [**Python in de klas**](http://pythonindeklas.nl/)
-("Python in the classroom") in such a way that these existing lessons can be
-executed with Hedy instead of with Python.
-
-### Level 1: Printing and input
-
-At the first level, students can firstly print text. For this, no
-syntactic elements are needed other than the keyword [`print`]
-followed by arbitrary text. Furthermore students can ask for
-input of the user using the keyword [`ask`]. Here we decided to use
-the keyword [`ask`] rather than [`input`] because it is more aligned
-with what the role of the keyword is in the code than with what it
-*does*. Input of a user can be repeated with [`echo`], so very simple
-programs can be created in which a user is asked for a name or a
-favorite animal, fulfilling Design Goal 6.
-
-### Level 2: Variables with is
-
-At the second level, variables are added to the syntax. Defining a
-variable is done with the word [`is`] rather than the equals symbol
-fulfilling Design Goal 3 and Design Goal 4. We also add the option to
-create lists and retrieve elements, including random elements from lists
-with [`at`]. Adding lists and especially adding the option to select a
-random item from a list allows for the creation of more interesting
-programs such as a guessing game, a story with random elements, which is
-an assignment from [**Python in de klas**](http://pythonindeklas.nl/)
-("Python in the classroom"), or a customized dice.
-
-### Level 3: Quotation marks and types
-In Level 3 the first syntactic element is introduced: the use of
-quotation marks to distinguish between strings and text. In teaching
-novices we have seen that this distinction can be confusing for a long
-time, so offering it early might help to draw attention to the fact that
-computers need information about the types of variables. This level is
-thus an interesting combination of explaining syntax and explaining
-programming concepts, which underlines their interdependency. The
-variable syntax using [`is`] remains unchanged, meaning that learners
-can now use both [`number is 12`] and [`name is Hedy`].
-
-### Level 4: Selection with if and else flat
-
-In Level 5, selection with the if statement is introduced, but the
-syntax is 'flat', i.e. placed on one line, resembling a regular syntax
-more:\
-[`if name is print `]\
-Else statements are also included, and are also placed on one line,
-using the keyword [`else`]:\
-[`if name is print else print `].
-
-### Level 5: Repetition with repeat x times
-
-In working with non-English native Python novices. Research has found
-the keyword [`for`] to be a confusing word for repetition, especially
-because it sounds like the word 'four' [@hermans_code_2018]. For our
-first simplest form, according to Design Goal 2, we opt to use
-Quorum [@stefik_quorum_2017] syntax [`repeat x times`]. In this
-initial form, like the if the syntax is placed on one line:\
-[`repeat 5 times print `]
-
-### Level 6: Calculations
-
-*Note: this level was originally planed as 4, is now moved up to 6.
-Might be moved to another place based on experiences of kids testing now.*
-
-In Level 4, students learn to calculate with variables, so addition,
-multiplication, subtraction and division are introduced. While this
-might seem like a simple step, our experience taught us that the use of
-[`*`] for multiplication, rather than $\times$, and the use of a
-period rather than a comma as decimal separator for non-US students is a
-steep learning curve and should be treated as a separate learning goal.
-
-
-### Level 7: Code blocks
-
-After Level 6, there is a clear need to 'move on', as the body of a loop
-(and also that of an if) can only consist of one line, which limits the
-possibilities of programs that users can create. We assume this
-limitation will be a motivating factor for learners, rather than 'having
-to learn' the block structure of Python, they are motivated by the
-prospect of building larger and more interesting programs (Design Goal
-6). The syntax of the loop remains otherwise unchanged as per Design
-Goal 3, so the new form is:\
-
-[`repeat 5 times`]\
-[`print `]\
-[`print `]\
-
-### Level 8: For syntax
-
-Once blocks are sufficiently automatized, learners will see a more
-Python-like form of the for loop, namely: [`for i in range 0 to 5`].
-This allows for access to the loop variable [`i`] and this allows for
-more interesting programs, such as counting to 10. As per Design Goal 3,
-the change is made small, and to do so (following Design Goal 4),
-brackets and colons are deferred to a later level, but indentation which
-was learned in Level 7 remains.
-
-### Level 9: Learning the colon
-
-To make the step to full Python, learners will need to use the colon to
-denote the beginning of a block, in both loops and conditionals. Because
-blocks are already known, we can teach learners to use a colon before
-every indentation, and have them practice that extensively.
-
-### Level 10: Repetition and selection nested
-
-To allow for enough interleaving of concepts (Design Goal 5), we defer
-the introduction of round brackets and focus on more conceptual
-additions: the nesting of blocks. We know indentation is a hard concept
-for students to learn, so this warrants its own level (Design Goal 3).
-
-### Level 11: Adding round brackets
-
-Level 11 adds round brackets in [`print`], [`range`] and
-[`input`]. As per Design Goal 4, these are added as late as possible.
-
-### Level 12: Adding rectangular brackets
-
-In level 12, learners encounter different types of brackets for the
-first time, because it adds rectangular brackets for list access, which
-up to now was done with the keyword [`at`], following Design Goal 2.
-
-### Level 13: Booleans
-
-In level 13, booleans are added. Learners encounter True and False and how to use them in if statements
-
-### Level 14: And and or
-
-In level 14, Learners learn about and and or in if statements.
-
-### Level 15: Comments
-
-In level 15, comments are introduced. The learner will now know how to comment code
-
-### Level 16: Smaller and bigger
-
-In level 16, Learners learn about < and > in preparation for while loops
-
-### Level 17: While loops
-
-In level 17, learners are introduced to the while loop. With the previous knowledge of booleans and < and >, learners
-can make basic while loops.
-
-### Level 18: Access specific value in list
-
-In level 18, learners are shown how to get a specific value from a list. The code to access a specific
-value has already been available for a while but there was no explanation yet how to access a specific
-value.
-
-### Level 19: Loop through all values in lists
-
-In level 19, learners are shown how to loop through a list. The length() function is also introduced,
-as it makes looping through a list easier. The code to loop through a list has already been available since
-the for loop was introduced but there was no explanation yet how to loop through the list.
-
-### Level 20: Change is to = and ==
-
-In level 20, we introduce the = and ==. All variable assignments change is to =. All equality checks
-turn into ==.
-
-### Level 21: Introducing !=
-
-In level 21, we introduce the != in the equality checks. This is introduced after the change to = and
-== as to make it easier to understand when you already know the syntax for =.
-
-### Level 22: Introducing <= and >=
-
-In level 22, we introduce <= and >=. This is introduced after the change to = and
-== as to make it easier to understand when you already know the syntax for =.
-
 Technical Design
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