A Pirozzo matrix of activities for early finishers in the Science classroom. This product is differentiated for different types of learners and different blooms orders of thinking.
I have all students stick it in the backs of their books and when they have finished early (and I have not other extension activities for them) they complete an activity from the grid. The idea for students is to get bingo by completing five activities in a row.
I have used this pirozzo grid with students from grade 7 to grade 10 and it is adapted to work with any science concept. Many of the tasks require students to create, engaging them in higher order thinking in the same learning objective as the rest of the class.
This follows the philosophy that you should differentiate out and not up for gifted students. Instead of giving them the next piece of work or the next grade levels work, have them engage in higher order thinking within the same concept the rest of the class is studying.
I have found this resource invaluable and I'm happy to offer it to you for free.