diff --git a/app/src/main/res/drawable/lesson_thumbnail_graphic_baker.xml b/app/src/main/res/drawable/lesson_thumbnail_graphic_baker.xml
new file mode 100644
index 00000000000..0f1813c6e44
--- /dev/null
+++ b/app/src/main/res/drawable/lesson_thumbnail_graphic_baker.xml
@@ -0,0 +1,551 @@
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diff --git a/app/src/main/res/drawable/lesson_thumbnail_graphic_child_with_book.xml b/app/src/main/res/drawable/lesson_thumbnail_graphic_child_with_book.xml
new file mode 100644
index 00000000000..efdefc0bebc
--- /dev/null
+++ b/app/src/main/res/drawable/lesson_thumbnail_graphic_child_with_book.xml
@@ -0,0 +1,79 @@
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diff --git a/app/src/main/res/drawable/lesson_thumbnail_graphic_child_with_cupcakes.xml b/app/src/main/res/drawable/lesson_thumbnail_graphic_child_with_cupcakes.xml
new file mode 100644
index 00000000000..48a0fcd37c7
--- /dev/null
+++ b/app/src/main/res/drawable/lesson_thumbnail_graphic_child_with_cupcakes.xml
@@ -0,0 +1,171 @@
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diff --git a/app/src/main/res/drawable/lesson_thumbnail_graphic_child_with_fractions_homework.xml b/app/src/main/res/drawable/lesson_thumbnail_graphic_child_with_fractions_homework.xml
new file mode 100644
index 00000000000..e5bd078ac52
--- /dev/null
+++ b/app/src/main/res/drawable/lesson_thumbnail_graphic_child_with_fractions_homework.xml
@@ -0,0 +1,344 @@
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diff --git a/app/src/main/res/drawable/lesson_thumbnail_graphic_duck_and_chicken.xml b/app/src/main/res/drawable/lesson_thumbnail_graphic_duck_and_chicken.xml
new file mode 100644
index 00000000000..f8a60005128
--- /dev/null
+++ b/app/src/main/res/drawable/lesson_thumbnail_graphic_duck_and_chicken.xml
@@ -0,0 +1,134 @@
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diff --git a/app/src/main/res/drawable/lesson_thumbnail_graphic_person_with_pie_chart.xml b/app/src/main/res/drawable/lesson_thumbnail_graphic_person_with_pie_chart.xml
new file mode 100644
index 00000000000..48b5b8b553b
--- /dev/null
+++ b/app/src/main/res/drawable/lesson_thumbnail_graphic_person_with_pie_chart.xml
@@ -0,0 +1,100 @@
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diff --git a/model/src/main/proto/thumbnail.proto b/model/src/main/proto/thumbnail.proto
new file mode 100644
index 00000000000..b2acda16257
--- /dev/null
+++ b/model/src/main/proto/thumbnail.proto
@@ -0,0 +1,40 @@
+syntax = "proto3";
+
+package model;
+
+option java_package = "org.oppia.app.model";
+option java_multiple_files = true;
+
+// Represents the thumbnail that should be rendered for a lesson.
+message LessonThumbnail {
+ // The graphic corresponding to this thumbnail.
+ LessonThumbnailGraphic thumbnail_graphic = 1;
+
+ // The background color for this thumbnail, in RGB (no alpha channel).
+ int32 background_color_rgb = 2;
+}
+
+// Corresponds to different types of thumbnails that may be used by a topic, story, or chapter. These currently only
+// correspond to in-app thumbnails, but may later indicate that a lesson has a downloadable thumbnail to use, instead.
+enum LessonThumbnailGraphic {
+ // An unknown thumbnail type. The UI should pick a reasonable default.
+ LESSON_THUMBNAIL_GRAPHIC_UNSPECIFIED = 0;
+
+ // Corresponds to an in-app image of a baker.
+ BAKER = 1;
+
+ // Corresponds to an in-app image of a child with a book.
+ CHILD_WITH_BOOK = 2;
+
+ // Corresponds to an in-app image of a child with cupcakes.
+ CHILD_WITH_CUPCAKES = 3;
+
+ // Corresponds to an in-app image of a child holding a homework paper with fractions.
+ CHILD_WITH_FRACTIONS_HOMEWORK = 4;
+
+ // Corresponds to an in-app image of a duck and a chicken.
+ DUCK_AND_CHICKEN = 5;
+
+ // Corresponds to an in-app image of a person next to a pie chart.
+ PERSON_WITH_PIE_CHART = 6;
+}