finish second lesson

docs/projects.md

@@ -1,5 +1,7 @@
 # Projects
 
+![](/static/mb/projects/all10.png)
+
 ![](/static/mb/projects/a1-display.png)
 
 [Flashing Heart](/projects/flashing-heart)

docs/projects/buttons-smiley.md

@@ -0,0 +1,67 @@
+![](/static/mb/projects/a2-buttons.png)
+
+Use buttons to show a smiley or frowny face. 
+
+## Step 1
+
+Use [show leds](/reference/basic/showLeds) to make a smiley face:
+
+```blocks
+basic.showLeds(`
+. # . # .
+. # . # .
+. . . . .
+# . . . #
+. # # # .`);
+```
+
+## Step 2
+
+Add an input block for when [button A is pressed](/reference/input/button-is-pressed), and put a
+frowny face inside it:
+
+```blocks
+basic.showLeds(`
+. # . # .
+. # . # .
+. . . . .
+# . . . #
+. # # # .`);
+input.onButtonPressed(Button.A, () => { 
+    basic.showLeds(`
+    . # . # .
+    . # . # .
+    . . . . .
+    . # # # .
+    # . . . #`);
+});
+```
+
+## Step 3
+
+Now add blocks so that when [button B is pressed](/reference/input/button-is-pressed), a smiley appears:
+
+```blocks
+basic.showLeds(`
+. # . # .
+. # . # .
+. . . . .
+# . . . #
+. # # # .`);
+input.onButtonPressed(Button.A, () => { 
+    basic.showLeds(`
+    . # . # .
+    . # . # .
+    . . . . .
+    . # # # .
+    # . . . #`);
+});
+input.onButtonPressed(Button.B, () => { 
+    basic.showLeds(`
+    . # . # .
+    . # . # .
+    . . . . .
+    # . . . #
+    . # # # .`);
+});
+```

docs/projects/flashing-heart.md

@@ -45,4 +45,50 @@ basic.showLeds(`
 basic.pause(500);
 basic.clearScreen();
 })
+```
+
+## Step 4
+
+Add a [pause](/reference/basic/pause) to wait after clearing the screen.
+
+```blocks
+basic.forever(() => {
+basic.showLeds(`
+. # . # .
+# # # # #
+# # # # #
+. # # # .
+. . # . .`);
+basic.pause(500);
+basic.clearScreen();
+basic.pause(500);
+})
+```
+
+## Step 5
+
+Add a second image of a broken heart. 
+
+
+```blocks
+basic.forever(() => {
+basic.showLeds(`
+. # . # .
+# # # # #
+# # # # #
+. # # # .
+. . # . .`);
+basic.pause(500);
+basic.clearScreen();
+basic.pause(500);
+basic.showLeds(`
+. # . # .
+# . # # #
+# . . . #
+. # # # .
+. . # . .`);
+basic.pause(500);
+basic.clearScreen();
+basic.pause(500);
+})
 ```