In Class 7 mathematics for the ICSE curriculum, algebraic expressions are introduced as a fundamental concept. Here’s a summary of what you might learn:

1. **Basic Concepts**: Understanding variables, constants, and coefficients. Learning to differentiate between terms and factors.

2. **Operations**: Performing operations like addition, subtraction, multiplication, and division on algebraic expressions.

3. **Simplification**: Simplifying algebraic expressions by combining like terms and using the distributive property.

4. **Expanding and Factoring**: Learning to expand and factorize simple algebraic expressions.

5. **Use in Real-Life Situations**: Understanding how to formulate and solve simple problems using algebraic expressions.

6. **Equations**: Introduction to basic equations and their solutions involving one variable.

7. **Word Problems**: Solving word problems involving algebraic expressions.

These topics serve as a foundation for more advanced algebraic concepts in higher classes.