This activity provides a variety of equations in one variable. The equations are listed in increasing difficulty, beginning with one-step solutions on through word problems. Although this file is labelled as the teacher copy, it is very similar to the student copy and does not contain answer keys. In addition, the solution needs to be entered exactly (numbers, symbols, spacing & order) to get the feedback "correct". Providing answer keys would improve this activity. Also, using it as a printed worksheet, rather than an interactive activity, would eliminate the need for exact matching the expected answer.