Use visuals and pictures to represent math problems, especially word problems. If possible, let students touch objects as well. A student can recognize what an automobile looks like visually, even if he doesn't know the word 'automobile.' Link word problems with visuals to surmount the ESL barrier. For example, with a toy car and a map of the United States, you could more easily communicate problems based on mileage or travel time.
Create quadrant cards out of index cards for your math story problems. Print one element (visual, math problem, equation, and new vocabulary) in each quadrant so that the student can grasp the information quickly.
Divide students into groups and have higher-performing ESL students explain the word problem to less capable students. Give each group of students a math word problem with different vocabulary and contexts. Encourage students to discuss the problems in their own language through translation. Require each group to present its answers back to the class in English.
Combine math problems with assignments covering new vocabulary and the context of the information. Present a math problem only after students understand the new material. Tell a story about baking enough cakes for a school party, for example, and have the characters in the story describe how they calculated the correct number of cakes. Require students to solve a similar word problem with different answers using a different operation (subtraction rather than addition, for example).