april 4

- Find:

• 2x4-1x5=3;
• 3x5-2x6=
• 4x6-3x7=
• ....
• 322x324-321x325=
• ....
• (a+1)(a+3)-a(a+4)=

- Look up the lunar eclipses over the past 20 years. On what months do they happen?


- Puzzle: guess what's in the picture?

Try to make your own picture of something that is hard to guess...