A series of ten interactive lessons that use the particle model
of matter to explain why ice floats, why bridges have gaps, how thermometers
work, and how forces change everything. Built for curious kids in grades 5–8.
Best read in order — each lesson builds on the one before.
Interactive lessons on Grade 7 & 8 Number — from the symmetry of the
number line to the full real number system with rational and irrational numbers. More units coming soon.