Search every subject world, from Preschool to Grade 12. The first five courses of every subject path are free.
8 courses
Science · Grade 3
Third graders learn to plan investigations like scientists: identify the one variable to change, the variables to keep the same and the result to measure. Using a ramp simulation with two variables (ramp height and floor surface), they spot unfair tests, collect repeated trials in a table, find the middle value and write a conclusion the data actually supports.
Science · Grade 3
Every push or pull has a strength and a direction. Learners draw force arrows, discover that balanced forces leave motion unchanged while unbalanced forces start, stop, speed up, slow down or turn objects, and explain a tug-of-war and a stuck box. Then they time a pendulum in a simulation, find the pattern in their measurements and use it to predict future motion.
Science · Grade 3
Magnets can push and pull without touching. Learners test which materials a magnet attracts (only some metals!), discover that like poles repel and opposite poles attract, and gather data showing the magnetic pull gets weaker with distance. They meet static electricity as another force that acts without touching, then define and compare designs for a problem that magnets can solve.
Science · Grade 3
A butterfly, a frog, a bean plant and a dog all have life cycles: birth, growth, reproduction and death. Learners build and label life-cycle models, compare cycles that include dramatic changes in body shape with cycles where the young look like small adults, and analyze data from puppy litters and rabbit families to show that traits are inherited from parents and vary within a group.
Science · Grade 3
Why do brown beetles survive better than green beetles on brown tree bark? Learners use data to explain how small differences between individuals of the same kind can help some survive and have more offspring. They find evidence that the environment also shapes traits (plants grown in shade stay shorter), and argue that living in groups helps animals such as wolves, fish and meerkats survive.
Science · Grade 3
Fish fossils on a mountaintop? Fern fossils in icy Antarctica? Learners discover how fossils form and use them as evidence of what lived long ago and what the environment was like. They argue why, in any habitat, some living things survive well, some less well and some not at all, and evaluate solutions to problems that arise when a habitat changes, such as a road cutting through a forest.
Science · Grade 3
Learners turn weather records into tables and graphs to describe the weather a town can expect in each season, then tell weather (today) from climate (the pattern over many years) and compare climates around the world. Finally they evaluate designs that reduce the damage from weather hazards, such as flood barriers, storm shutters and lightning rods, using evidence and tradeoffs.
Science · Grade 3
The class needs a package that keeps a fragile cracker from breaking when it is dropped. Learners define the problem with criteria and constraints, compare three designs in a decision table, run fair drop tests to find each design's failure points, improve the best one and defend their final choice with evidence, the way real engineering teams do.
