Theme Lessons with EnglishClub
Below you'll find ten common themes that ESL teachers use. If you use a theme-based textbook, you can supplement your curriculum with EnglishClub activities to keep your students interested. Your themes may be slightly different from the ones listed here. For example, Chapter One of your textbook might be called, "Getting around Town". If this is the case, you may be able to use some exercises from the following themes, such as an activity on money. A Unit called "The Human Body" may be suitable for activities on clothing or health. If you have to gather all of your own materials rather than having a core textbook, you might want to try teaching with themes. While not all activities will be suitable for the level or size of your class, you can adapt or sort through them to find the ones you like best. Some activities make great homework assignments or quizzes, while others can be used for a full class lesson. A number of these activities come from TEFL.net which is a part of the EnglishClub group.
Animals
Animal Idioms - with examples and quiz
Children's Story about farm Animals - with vocab and quiz 
Children's Story about animals from different regions - with vocab and quiz
Animals and Animosity: Idioms, Gap Fill, Discussion Questions
Animals and the Environment: Vocabulary, Paired Discussion
Clothing
Clothing Idioms: Definitions, Examples, Quiz
What am I wearing? Group Games
A Wolf in Sheep's Clothing: Reading and Quiz
A Wolf in Sheep's Clothing: Pair Activities
Food
Food Idioms: Definitions, Examples, Quiz
Working in the Food Industry: Vocabulary, Dialogues, Quiz
Food Crossword Puzzles: Computer
Food Matching Puzzle: Computer
Food Habits and Holidays: Pair Activity
Geography
Geography Crossword Puzzles: Computer
Geography Matching Puzzles: Computer
Children's Story about animals from different regions, with vocab and questions
British vs. American Vocabulary
Geography Idioms: Definitions, Examples, Quiz
Country; Nationality; Language: Worksheet
ESL World Section: Information about various countries where ESL is taught
Holidays and Travel
Children's Story about Animals Taking a Holiday: Story, Vocabulary, Quizzes
Working in the Tourism Industry: Vocabulary, Dialogues, Quizzes
Working in the Hotel Industry: Vocabulary, Dialogues, Quizzes
Is Halloween Harmful: Discussion, Matching
Tourism and Holidays: Partner Discussion
Christmas-A Global Phenomenon: Pair Activity
The First Christmas Card: Reading
Christmas Conversations: Practice Past, Present, Future
Christmas Games: True and False; Unjumble
Christmas: Vocabulary and Pair Conversation
Holidays and Hotels: Pair Activity
Holidays-Phrases and Places: Gap; Matching; Conversation
Holiday Word Partners: Pair Activity
Jobs
EnglishClub section on Using English in the Workplace
EnglishClub section on Business English
How to Write a Resume and Cover Letter
Writing Cover Letters: Reading
Numbers and Money
Business English: Money; World Currencies, Currency Converter
Discussion Topic: Defining Success
Numbers Crossword Puzzle: Computer
Currencies Matching Game online
Sports and Health
Phrasal Verbs: Many verbs used in sports
The Tortoise and the Hare: Reading
Working in the Medical Industry: Vocabulary, Dialogues, Quizzes
Sports Idioms: Definitions, Examples, Quiz
Body Idioms: Definitions, Examples, Quiz
The Olympic Games: Conversation Practice
Is Football a Waste of Time: Conversation Practice
Technology
Science and Technology Crosswords
Self Study=Distance Learning: Article
Weather
Lesson on Weather: Vocabulary, Dialogues, Quizzes
Geography and Weather Idioms: Definitions, Examples, Quiz
Weather Crossword Puzzle: Computer
Avalanches: Reading and Fill-in-blanks
Natural Disasters: Pair Activity
Let it Snow: Conversation, Vocabulary, Gap
Children's story about building a snowman: Story, Vocabulary, Quizzes
If you have other themes that you need lessons and activities for, type your topic into EnglishClub search and sort through the results. If it is a common theme used in ESL you will likely find plenty of teaching aids by doing this.