diff --git a/src/actions/actionTypes.ts b/src/actions/actionTypes.ts
index 735b1a65c0..536d1fdee9 100644
--- a/src/actions/actionTypes.ts
+++ b/src/actions/actionTypes.ts
@@ -13,8 +13,6 @@ export const CLEAR_REPL_INPUT = 'CLEAR_REPL_INPUT'
 export const CLEAR_REPL_OUTPUT = 'CLEAR_REPL_OUTPUT'
 export const CLEAR_CONTEXT = 'CLEAR_CONTEXT'
 export const SEND_REPL_INPUT_TO_OUTPUT = 'SEND_REPL_INPUT_TO_OUTPUT'
-export const CHAPTER_SELECT = 'CHAPTER_SELECT'
-export const CHANGE_CHAPTER = 'CHANGE_CHAPTER'
 
 /** Interpreter */
 export const HANDLE_CONSOLE_LOG = 'HANDLE_CONSOLE_LOG'
diff --git a/src/actions/playground.ts b/src/actions/playground.ts
index 39b772f22c..c900fe6437 100644
--- a/src/actions/playground.ts
+++ b/src/actions/playground.ts
@@ -1,4 +1,3 @@
-import { ChangeEvent } from 'react'
 import { ActionCreator } from 'redux'
 import * as actionTypes from './actionTypes'
 
@@ -20,18 +19,6 @@ export const sendReplInputToOutput: ActionCreator<actionTypes.IAction> = (newOut
   }
 })
 
-export const chapterSelect: ActionCreator<actionTypes.IAction> = (
-  e: ChangeEvent<HTMLSelectElement>
-) => ({
-  type: actionTypes.CHAPTER_SELECT,
-  payload: e.currentTarget.value
-})
-
-export const changeChapter: ActionCreator<actionTypes.IAction> = (newChapter: number) => ({
-  type: actionTypes.CHANGE_CHAPTER,
-  payload: newChapter
-})
-
 export const evalEditor = () => ({
   type: actionTypes.EVAL_EDITOR
 })
diff --git a/src/components/IDE/Control.tsx b/src/components/IDE/Control.tsx
index c366f58028..39523903ca 100644
--- a/src/components/IDE/Control.tsx
+++ b/src/components/IDE/Control.tsx
@@ -1,7 +1,6 @@
-import { Button, IconName, Intent } from '@blueprintjs/core'
 import * as React from 'react'
 
-import { sourceChapters } from '../../reducers/states'
+import { Button, IconName, Intent } from '@blueprintjs/core'
 
 /**
  * @property handleEvalEditor  - A callback function for evaluation
@@ -11,40 +10,26 @@ export interface IControlProps {
   handleEvalEditor: () => void
   handleEvalRepl: () => void
   handleClearReplOutput: () => void
-  handleChapterSelect: (e: React.ChangeEvent<HTMLSelectElement>) => void
 }
 
-const genericButton = (
-  label: string,
-  icon: IconName,
-  handleClick = () => {},
-  intent = Intent.NONE,
-  notMinimal = false
-) => (
-  <Button
-    onClick={handleClick}
-    className={(notMinimal ? '' : 'pt-minimal') + ' col-xs-12'}
-    intent={intent}
-    icon={icon}
-  >
-    {label}
-  </Button>
-)
-
-const chapterSelect = (handleSelect = (e: React.ChangeEvent<HTMLSelectElement>) => {}) => (
-  <div className="col-xs-4 pt-select pt-select">
-    <select defaultValue={sourceChapters.slice(-1)[0].toString()} onChange={handleSelect}>
-      {sourceChapters.map(chap => (
-        <option key={chap} value={chap}>
-          {`Source \xa7${chap}`}
-        </option>
-      ))}
-    </select>
-  </div>
-)
-
 class Control extends React.Component<IControlProps, {}> {
   public render() {
+    const genericButton = (
+      label: string,
+      icon: IconName,
+      handleClick = () => {},
+      intent = Intent.NONE,
+      notMinimal = false
+    ) => (
+      <Button
+        onClick={handleClick}
+        className={(notMinimal ? '' : 'pt-minimal') + ' col-xs-12'}
+        intent={intent}
+        icon={icon}
+      >
+        {label}
+      </Button>
+    )
     const runButton = genericButton('Run', 'play', this.props.handleEvalEditor)
     const evalButton = genericButton('Eval', 'play', this.props.handleEvalRepl)
     const clearButton = genericButton('Clear', 'remove', this.props.handleClearReplOutput)
@@ -53,9 +38,8 @@ class Control extends React.Component<IControlProps, {}> {
         <div className="col-xs-2">{runButton}</div>
         <div className="col-xs-4">
           <div className="row">
-            {chapterSelect(this.props.handleChapterSelect)}
-            <div className="col-xs-4">{evalButton}</div>
-            <div className="col-xs-4">{clearButton}</div>
+            <div className="col-xs-6">{evalButton}</div>
+            <div className="col-xs-6">{clearButton}</div>
           </div>
         </div>
       </div>
diff --git a/src/components/IDE/__tests__/Control.tsx b/src/components/IDE/__tests__/Control.tsx
index ada0fe6e1a..2a2c8646b3 100644
--- a/src/components/IDE/__tests__/Control.tsx
+++ b/src/components/IDE/__tests__/Control.tsx
@@ -8,8 +8,7 @@ test('Control renders correctly', () => {
   const props: IControlProps = {
     handleEvalEditor: () => {},
     handleEvalRepl: () => {},
-    handleClearReplOutput: () => {},
-    handleChapterSelect: (e: React.ChangeEvent<HTMLSelectElement>) => {}
+    handleClearReplOutput: () => {}
   }
   const app = <Control {...props} />
   const tree = shallow(app)
diff --git a/src/components/IDE/__tests__/__snapshots__/Control.tsx.snap b/src/components/IDE/__tests__/__snapshots__/Control.tsx.snap
index 1dc888996b..162ba7418a 100644
--- a/src/components/IDE/__tests__/__snapshots__/Control.tsx.snap
+++ b/src/components/IDE/__tests__/__snapshots__/Control.tsx.snap
@@ -9,22 +9,12 @@ exports[`Control renders correctly 1`] = `
   </div>
   <div className=\\"col-xs-4\\">
     <div className=\\"row\\">
-      <div className=\\"col-xs-4 pt-select pt-select\\">
-        <select defaultValue=\\"2\\" onChange={[Function: handleChapterSelect]}>
-          <option value={1}>
-            Source §1
-          </option>
-          <option value={2}>
-            Source §2
-          </option>
-        </select>
-      </div>
-      <div className=\\"col-xs-4\\">
+      <div className=\\"col-xs-6\\">
         <Blueprint2.Button onClick={[Function: handleEvalRepl]} className=\\"pt-minimal col-xs-12\\" intent=\\"none\\" icon=\\"play\\">
           Eval
         </Blueprint2.Button>
       </div>
-      <div className=\\"col-xs-4\\">
+      <div className=\\"col-xs-6\\">
         <Blueprint2.Button onClick={[Function: handleClearReplOutput]} className=\\"pt-minimal col-xs-12\\" intent=\\"none\\" icon=\\"remove\\">
           Clear
         </Blueprint2.Button>
diff --git a/src/containers/IDE/ControlContainer.ts b/src/containers/IDE/ControlContainer.ts
index d76e3a9d57..bf0102f302 100644
--- a/src/containers/IDE/ControlContainer.ts
+++ b/src/containers/IDE/ControlContainer.ts
@@ -1,14 +1,13 @@
 import { connect, MapDispatchToProps, MapStateToProps } from 'react-redux'
 import { bindActionCreators, Dispatch } from 'redux'
 
-import { chapterSelect, clearReplOutput, evalEditor, evalRepl } from '../../actions/playground'
+import { clearReplOutput, evalEditor, evalRepl } from '../../actions/playground'
 import Control, { IControlProps } from '../../components/IDE/Control'
 import { IState } from '../../reducers/states'
 
 type DispatchProps = Pick<IControlProps, 'handleEvalEditor'> &
   Pick<IControlProps, 'handleEvalRepl'> &
-  Pick<IControlProps, 'handleClearReplOutput'> &
-  Pick<IControlProps, 'handleChapterSelect'>
+  Pick<IControlProps, 'handleClearReplOutput'>
 
 /** No-op mapStateToProps */
 const mapStateToProps: MapStateToProps<{}, {}, IState> = state => ({})
@@ -21,8 +20,7 @@ const mapDispatchToProps: MapDispatchToProps<DispatchProps, {}> = (dispatch: Dis
     {
       handleEvalEditor: evalEditor,
       handleEvalRepl: evalRepl,
-      handleClearReplOutput: clearReplOutput,
-      handleChapterSelect: chapterSelect
+      handleClearReplOutput: clearReplOutput
     },
     dispatch
   )
diff --git a/src/mocks/context.ts b/src/mocks/context.ts
index ded2dfc7df..12ecd4c6f7 100644
--- a/src/mocks/context.ts
+++ b/src/mocks/context.ts
@@ -1,6 +1,6 @@
 import { createContext } from '../slang'
 import { Context } from '../slang/types'
 
-export function mockContext(chapter = 1): Context {
-  return createContext(chapter)
+export function mockContext(): Context {
+  return createContext()
 }
diff --git a/src/reducers/playground.ts b/src/reducers/playground.ts
index 9829faa415..c42e4a45ab 100644
--- a/src/reducers/playground.ts
+++ b/src/reducers/playground.ts
@@ -1,6 +1,5 @@
 import { Reducer } from 'redux'
 import {
-  CHANGE_CHAPTER,
   CLEAR_CONTEXT,
   CLEAR_REPL_INPUT,
   CLEAR_REPL_OUTPUT,
@@ -42,12 +41,7 @@ export const reducer: Reducer<IPlaygroundState> = (state = defaultPlayground, ac
     case CLEAR_CONTEXT:
       return {
         ...state,
-        context: createContext(state.sourceChapter)
-      }
-    case CHANGE_CHAPTER:
-      return {
-        ...state,
-        sourceChapter: action.payload
+        context: createContext()
       }
     case HANDLE_CONSOLE_LOG:
       /* Possible cases:
diff --git a/src/reducers/states.ts b/src/reducers/states.ts
index 843c0f2048..435cf2f790 100644
--- a/src/reducers/states.ts
+++ b/src/reducers/states.ts
@@ -11,11 +11,7 @@ export interface IApplicationState {
   readonly environment: ApplicationEnvironment
 }
 
-export const sourceChapters = [1, 2]
-const latestSourceChapter = sourceChapters.slice(-1)[0]
-
 export interface IPlaygroundState {
-  readonly sourceChapter: number
   readonly editorValue: string
   readonly replValue: string
   readonly context: Context
@@ -91,9 +87,8 @@ export const defaultApplication: IApplicationState = {
 }
 
 export const defaultPlayground: IPlaygroundState = {
-  sourceChapter: latestSourceChapter,
   editorValue: '',
   replValue: '',
-  context: createContext(latestSourceChapter),
+  context: createContext(),
   output: []
 }
diff --git a/src/sagas/index.ts b/src/sagas/index.ts
index 77077007e4..de6a26988b 100644
--- a/src/sagas/index.ts
+++ b/src/sagas/index.ts
@@ -6,7 +6,6 @@ import { Context, interrupt, runInContext } from '../slang'
 
 import * as actions from '../actions'
 import * as actionTypes from '../actions/actionTypes'
-import { showSuccessMessage } from '../notification'
 
 function* evalCode(code: string, context: Context) {
   const { result, interrupted } = yield race({
@@ -45,20 +44,6 @@ function* interpreterSaga(): SagaIterator {
     yield put(actions.sendReplInputToOutput(code))
     yield* evalCode(code, context)
   })
-
-  yield takeEvery(actionTypes.CHAPTER_SELECT, function*(action) {
-    const newChapter = parseInt((action as actionTypes.IAction).payload, 10)
-    const oldChapter = yield select((state: IState) => state.playground.sourceChapter)
-    if (newChapter !== oldChapter) {
-      yield put(actions.changeChapter(newChapter))
-      yield put(actions.handleInterruptExecution())
-      yield put(actions.clearContext())
-      yield put(actions.clearReplOutput())
-      yield call(showSuccessMessage, `Switched to Source \xa7${newChapter}`)
-    } else {
-      yield undefined
-    }
-  })
 }
 
 function* mainSaga() {
diff --git a/src/slang/createContext.ts b/src/slang/createContext.ts
index d958b515a9..b3191554cd 100644
--- a/src/slang/createContext.ts
+++ b/src/slang/createContext.ts
@@ -17,8 +17,8 @@ const createEmptyRuntime = () => ({
   nodes: []
 })
 
-export const createEmptyContext = (chapter: number): Context => ({
-  chapter,
+export const createEmptyContext = (week: number): Context => ({
+  week,
   errors: [],
   cfg: createEmptyCFG(),
   runtime: createEmptyRuntime()
@@ -56,7 +56,7 @@ export const importExternals = (context: Context, externals: string[]) => {
 export const importBuiltins = (context: Context) => {
   ensureGlobalEnvironmentExist(context)
 
-  if (context.chapter >= 1) {
+  if (context.week >= 3) {
     defineSymbol(context, 'runtime', misc.runtime)
     defineSymbol(context, 'display', misc.display)
     defineSymbol(context, 'error', misc.error_message)
@@ -79,15 +79,22 @@ export const importBuiltins = (context: Context) => {
     }
   }
 
-  if (context.chapter >= 2) {
-    // List library
+  if (context.week >= 4) {
+    defineSymbol(context, 'math_log', Math.log)
+    defineSymbol(context, 'math_exp', Math.exp)
+    defineSymbol(context, 'alert', alert)
+    defineSymbol(context, 'math_floor', Math.floor)
+    defineSymbol(context, 'timed', misc.timed)
+  }
+
+  if (context.week >= 5) {
+    defineSymbol(context, 'list', list.list)
     defineSymbol(context, 'pair', list.pair)
     defineSymbol(context, 'is_pair', list.is_pair)
+    defineSymbol(context, 'is_list', list.is_list)
+    defineSymbol(context, 'is_empty_list', list.is_empty_list)
     defineSymbol(context, 'head', list.head)
     defineSymbol(context, 'tail', list.tail)
-    defineSymbol(context, 'is_empty_list', list.is_empty_list)
-    defineSymbol(context, 'is_list', list.is_list)
-    defineSymbol(context, 'list', list.list)
     defineSymbol(context, 'length', list.length)
     defineSymbol(context, 'map', list.map)
     defineSymbol(context, 'build_list', list.build_list)
@@ -98,20 +105,12 @@ export const importBuiltins = (context: Context) => {
     defineSymbol(context, 'member', list.member)
     defineSymbol(context, 'remove', list.remove)
     defineSymbol(context, 'remove_all', list.remove_all)
+    defineSymbol(context, 'equal', list.equal)
+    defineSymbol(context, 'assoc', list.assoc)
     defineSymbol(context, 'filter', list.filter)
     defineSymbol(context, 'enum_list', list.enum_list)
     defineSymbol(context, 'list_ref', list.list_ref)
     defineSymbol(context, 'accumulate', list.accumulate)
-    defineSymbol(context, 'equal', list.equal)
-  }
-
-  if (context.chapter >= Infinity) {
-    // previously week 4
-    defineSymbol(context, 'alert', alert)
-    defineSymbol(context, 'math_floor', Math.floor)
-    defineSymbol(context, 'timed', misc.timed)
-    // previously week 5
-    defineSymbol(context, 'assoc', list.assoc)
     if (window.hasOwnProperty('ListVisualizer')) {
       defineSymbol(context, 'draw', (window as any).ListVisualizer.draw)
     } else {
@@ -119,19 +118,22 @@ export const importBuiltins = (context: Context) => {
         throw new Error('List visualizer is not enabled')
       })
     }
-    // previously week 6
+  }
+  if (context.week >= 6) {
     defineSymbol(context, 'is_number', misc.is_number)
-    // previously week 8
+  }
+  if (context.week >= 8) {
     defineSymbol(context, 'undefined', undefined)
     defineSymbol(context, 'set_head', list.set_head)
     defineSymbol(context, 'set_tail', list.set_tail)
-    // previously week 9
+  }
+  if (context.week >= 9) {
     defineSymbol(context, 'array_length', misc.array_length)
   }
 }
 
-const createContext = (chapter = 1, externals = []) => {
-  const context = createEmptyContext(chapter)
+const createContext = (week = 3, externals = []) => {
+  const context = createEmptyContext(week)
 
   importBuiltins(context)
   importExternals(context, externals)
diff --git a/src/slang/interop.ts b/src/slang/interop.ts
index 45030dbd24..082b8a6985 100644
--- a/src/slang/interop.ts
+++ b/src/slang/interop.ts
@@ -1,7 +1,7 @@
 import { generate } from 'astring'
 import { MAX_LIST_DISPLAY_LENGTH } from './constants'
 import { apply } from './interpreter'
-import { ArrowClosure, Closure, Context, Value } from './types'
+import { Closure, Context, Value } from './types'
 
 export const closureToJS = (value: Value, context: Context, klass: string) => {
   function DummyClass(this: Value) {
@@ -30,7 +30,7 @@ export const closureToJS = (value: Value, context: Context, klass: string) => {
 }
 
 export const toJS = (value: Value, context: Context, klass?: string) => {
-  if (value instanceof Closure || value instanceof ArrowClosure) {
+  if (value instanceof Closure) {
     return value.fun
   } else {
     return value
diff --git a/src/slang/parser.ts b/src/slang/parser.ts
index dcfa02e1e0..e975b8c564 100644
--- a/src/slang/parser.ts
+++ b/src/slang/parser.ts
@@ -10,7 +10,7 @@ import { Context, ErrorSeverity, ErrorType, SourceError } from './types'
 
 // tslint:disable-next-line:interface-name
 export interface ParserOptions {
-  chapter: number
+  week: number
 }
 
 export class DisallowedConstructError implements SourceError {
@@ -133,7 +133,7 @@ for (const type of Object.keys(syntaxTypes)) {
       usages: []
     }
     context.cfg.edges[id] = []
-    if (syntaxTypes[node.type] > context.chapter) {
+    if (syntaxTypes[node.type] > context.week) {
       context.errors.push(new DisallowedConstructError(node))
     }
   }
@@ -167,7 +167,7 @@ rules.forEach(rule => {
   const keys = Object.keys(rule.checkers)
   keys.forEach(key => {
     walkers[key] = compose(walkers[key], (node, context) => {
-      if (typeof rule.disableOn !== 'undefined' && context.chapter >= rule.disableOn) {
+      if (typeof rule.disableOn !== 'undefined' && context.week >= rule.disableOn) {
         return
       }
       const checker = rule.checkers[key]
diff --git a/src/slang/syntaxTypes.ts b/src/slang/syntaxTypes.ts
index 2ebbfb2c54..0efe756b42 100644
--- a/src/slang/syntaxTypes.ts
+++ b/src/slang/syntaxTypes.ts
@@ -1,40 +1,42 @@
 const syntaxTypes: { [nodeName: string]: number } = {
-  // Chapter 1
-  Program: 1,
-  ExpressionStatement: 1,
-  IfStatement: 1,
-  FunctionDeclaration: 1,
-  VariableDeclaration: 1,
-  ReturnStatement: 1,
-  CallExpression: 1,
-  UnaryExpression: 1,
-  BinaryExpression: 1,
-  LogicalExpression: 1,
-  ConditionalExpression: 1,
-  FunctionExpression: 1,
-  ArrowFunctionExpression: 1,
-  Identifier: 1,
-  Literal: 1,
-
-  // Chapter 2
-  ArrayExpression: 2,
+  // Week 3
+  Program: 3,
+  ExpressionStatement: 3,
+  IfStatement: 3,
+  FunctionDeclaration: 3,
+  VariableDeclaration: 3,
+  ReturnStatement: 3,
+  CallExpression: 3,
+  UnaryExpression: 3,
+  BinaryExpression: 3,
+  LogicalExpression: 3,
+  ConditionalExpression: 3,
+  FunctionExpression: 3,
+  ArrowFunctionExpression: 3,
+  Identifier: 3,
+  Literal: 3,
 
   // Week 5
   EmptyStatement: 5,
-  // preivously Week 8
+  ArrayExpression: 5,
+
+  // Week 8
   AssignmentExpression: 8,
   WhileStatement: 8,
-  // previously Week 9
+
+  // Week 9
   ForStatement: 9,
   BreakStatement: 9,
   ContinueStatement: 9,
   MemberExpression: 9,
-  // previously Week 10
+
+  // Week 10
   ThisExpression: 10,
   ObjectExpression: 10,
   Property: 10,
   UpdateExpression: 10,
   NewExpression: 10,
+
   // Disallowed Forever
   SwitchStatement: Infinity,
   DebuggerStatement: Infinity,
diff --git a/src/slang/types.ts b/src/slang/types.ts
index 338f44f985..6a9c186597 100644
--- a/src/slang/types.ts
+++ b/src/slang/types.ts
@@ -93,7 +93,7 @@ export interface TypeError extends SourceError {
 
 export interface Context {
   /** The source version used */
-  chapter: number
+  week: number
 
   /** All the errors gathered */
   errors: SourceError[]