Go to READ the DIRECTIONS Try Path 1 and Path 2 http://illuminations.nctm.org/LessonDetail.aspx?id=L396 READ the DIRECTIONS Try Path 1 and Path 2 Then figure out the shortest path to the pond Website on piece of paper at your desk

How to program the shortest path Press “clear” to erase To create a new path, adjust the length by using the blue sliders press the "forward", "back", or "turn" buttons to have it placed in the programming area Click “draw” to make it draw

Cryptography? Answers to our take home packet Selection of prizes "Cowards die many times before their deaths; the valiant never taste of death but once."

What numbers occur most frequently in the ciphertext? Frequency analysis is the process by which the frequency of a letter in an encoded messages is compared with the frequency of letters in English words.

What numbers occur most frequently in the ciphertext? For instance, the letter E occurs most often in English words, so if the letter W occurs most often in ciphertext, then it is likely that E has been replaced by W.

See Handout

Using the Frequency Table Decode this Message TFNRIUJ UZV DREP KZDVJ SVWFIV KYVZI UVRKYJ; KYV MRCZREK EVMVI KRJKV FW UVRKY SLK FETV. Which letter is used the most? "Cowards die many times before their deaths; the valiant never taste of death but once." By analyzing the ciphertext, students should notice the following: The letter V occurs the most times (13) in the ciphertext. The letter K occurs the second most times (9) in the ciphertext. The letter R occurs the third most times (7) in the ciphertext. The first five letters of word just before the semicolon are the same as the letters of the third word from the end: UVRKY. The most frequently occurring letters in English words are E (13.0%) and T (9.3%). By comparing these percents to the most frequent occurrences in the encoded message, it seems reasonable that E and T might have been replaced by V, K, or R. If the frequencies hold, then E was probably replaced by V, and T was likely replaced by K. Substituting these into the ciphertext reveals that the word just after the semicolon is T_E; this suggests that the middle letter is probably H, giving THE, so H was probably replaced by Y when the message was encoded. Continuing the same type of reasoning, the next five most common letters on the Letter Frequency chart are A, I, N, O, and R, all of which are just over 7%. These letters were probably replaced by the letters E, F, I, J, U, Y, and Z, all of which occur four times in the ciphertext. Students can use this information with some logic to begin putting letters in place. Eventually, some words will become obvious, and students can make guesses at the missing letters without using the frequency table. You may wish to guide students as they crack this code and decipher the message. While cracking this code, students may realize that the ciphertext was created by replacing each letter of plaintext with a letter 17 places ahead in the alphabet. In particular, A was replaced by R, B was replaced by S, C was replaced by T, and so forth. That is, a shift of 17 units was used. If students did not notice this, point it out to them.

Using the Frequency Table Decode this Message TFNRIUJ UZV DREP KZDVJ SVWFIV KYVZI UVRKYJ; KYV MRCZREK EVMVI KRJKV FW UVRKY SLK FETV. Which letter is used the most? "Cowards die many times before their deaths; the valiant never taste of death but once." By analyzing the ciphertext, students should notice the following: The letter V occurs the most times (13) in the ciphertext. The letter K occurs the second most times (9) in the ciphertext. The letter R occurs the third most times (7) in the ciphertext. The first five letters of word just before the semicolon are the same as the letters of the third word from the end: UVRKY. The most frequently occurring letters in English words are E (13.0%) and T (9.3%). By comparing these percents to the most frequent occurrences in the encoded message, it seems reasonable that E and T might have been replaced by V, K, or R. If the frequencies hold, then E was probably replaced by V, and T was likely replaced by K. Substituting these into the ciphertext reveals that the word just after the semicolon is T_E; this suggests that the middle letter is probably H, giving THE, so H was probably replaced by Y when the message was encoded. Continuing the same type of reasoning, the next five most common letters on the Letter Frequency chart are A, I, N, O, and R, all of which are just over 7%. These letters were probably replaced by the letters E, F, I, J, U, Y, and Z, all of which occur four times in the ciphertext. Students can use this information with some logic to begin putting letters in place. Eventually, some words will become obvious, and students can make guesses at the missing letters without using the frequency table. You may wish to guide students as they crack this code and decipher the message. While cracking this code, students may realize that the ciphertext was created by replacing each letter of plaintext with a letter 17 places ahead in the alphabet. In particular, A was replaced by R, B was replaced by S, C was replaced by T, and so forth. That is, a shift of 17 units was used. If students did not notice this, point it out to them.

Using the Frequency Table Decode this Message TFNRIUJ UZV DREP KZDVJ SVWFIV KYVZI UVRKYJ; KYV MRCZREK EVMVI KRJKV FW UVRKY SLK FETV. Which letter is used the most? The next most used letter? "Cowards die many times before their deaths; the valiant never taste of death but once." By analyzing the ciphertext, students should notice the following: The letter V occurs the most times (13) in the ciphertext. The letter K occurs the second most times (9) in the ciphertext. The letter R occurs the third most times (7) in the ciphertext. The first five letters of word just before the semicolon are the same as the letters of the third word from the end: UVRKY. The most frequently occurring letters in English words are E (13.0%) and T (9.3%). By comparing these percents to the most frequent occurrences in the encoded message, it seems reasonable that E and T might have been replaced by V, K, or R. If the frequencies hold, then E was probably replaced by V, and T was likely replaced by K. Substituting these into the ciphertext reveals that the word just after the semicolon is T_E; this suggests that the middle letter is probably H, giving THE, so H was probably replaced by Y when the message was encoded. Continuing the same type of reasoning, the next five most common letters on the Letter Frequency chart are A, I, N, O, and R, all of which are just over 7%. These letters were probably replaced by the letters E, F, I, J, U, Y, and Z, all of which occur four times in the ciphertext. Students can use this information with some logic to begin putting letters in place. Eventually, some words will become obvious, and students can make guesses at the missing letters without using the frequency table. You may wish to guide students as they crack this code and decipher the message. While cracking this code, students may realize that the ciphertext was created by replacing each letter of plaintext with a letter 17 places ahead in the alphabet. In particular, A was replaced by R, B was replaced by S, C was replaced by T, and so forth. That is, a shift of 17 units was used. If students did not notice this, point it out to them.

Using the Frequency Table Decode this Message TFNRIUJ UZV DREP KZDVJ SVWFIV KYVZI UVRKYJ; KYV MRCZREK EVMVI KRJKV FW UVRKY SLK FETV. Which letter is used the most? The next most used letter? "Cowards die many times before their deaths; the valiant never taste of death but once." By analyzing the ciphertext, students should notice the following: The letter V occurs the most times (13) in the ciphertext. The letter K occurs the second most times (9) in the ciphertext. The letter R occurs the third most times (7) in the ciphertext. The first five letters of word just before the semicolon are the same as the letters of the third word from the end: UVRKY. The most frequently occurring letters in English words are E (13.0%) and T (9.3%). By comparing these percents to the most frequent occurrences in the encoded message, it seems reasonable that E and T might have been replaced by V, K, or R. If the frequencies hold, then E was probably replaced by V, and T was likely replaced by K. Substituting these into the ciphertext reveals that the word just after the semicolon is T_E; this suggests that the middle letter is probably H, giving THE, so H was probably replaced by Y when the message was encoded. Continuing the same type of reasoning, the next five most common letters on the Letter Frequency chart are A, I, N, O, and R, all of which are just over 7%. These letters were probably replaced by the letters E, F, I, J, U, Y, and Z, all of which occur four times in the ciphertext. Students can use this information with some logic to begin putting letters in place. Eventually, some words will become obvious, and students can make guesses at the missing letters without using the frequency table. You may wish to guide students as they crack this code and decipher the message. While cracking this code, students may realize that the ciphertext was created by replacing each letter of plaintext with a letter 17 places ahead in the alphabet. In particular, A was replaced by R, B was replaced by S, C was replaced by T, and so forth. That is, a shift of 17 units was used. If students did not notice this, point it out to them.

Realign A B C D E F G H I J K L M N O P K R S T U V W X Y Z J K L M N O PQ R S T U V W X Y Z A B C D E F G H I

"Cowards die many times before their deaths; the valiant never taste of death but once."

Caesar Cipher

Caesar Cipher Coded English YVTL PZ AOL NYLHALZA LTWPYL. Decoded message = Rome was not built in a day. For the shift of 7 described above, students would use the Caesar shifter by rotating the letter A on the smaller circle so that it appears under the H on the larger circle. The number 7 above the H on the larger circle indicates that this is a shift of 7 units.

Caesar Cipher Starter

Caesar Cipher Starter Standard Alphabet: Caesar Alphabet: A B C D E F G H I J K L M N O P Q R S T U V W X Y Z Caesar Alphabet: X Y Z A B C D E F G H I J K L M N O P Q R S T U V W

Caesar Cipher Starter answers Message One PMFBP PBKA PBZOBQ JBPPXDBP. SPIES SEND SECRET MESSAGES. Message Two QEB XOJV FP LK QEB JLSB. THE ARMY IS ON THE MOVE. Message Three QELJXP GBCCBOPLK ABPFDKBA X PRYPQFQRQFLK ZFMEBO. THOMAS JEFFERSON DESIGNED A SUBSTITUTION CIPHER.

Easy Decode

Easy Decode Answers Can You Read This Secret Message

Intermediate Decode

Intermediate Decode Message One UJTUQJ FQQ FWTZSI YMJ BTWQI QNPJ YT XTQAJ UZEEQJX. Hint: HINT: Look for a pattern that would fit the word "PEOPLE." UJTUQJ FQQ FWTZSI YMJ BTWQI QNPJ YT XTQAJ UZEEQJX.

Intermediate Decode Hint: HINT: Look for a pattern that would fit the word "PEOPLE." UJTUQJ FQQ FWTZSI YMJ BTWQI QNPJ YT XTQAJ UZEEQJX. Try converting UJTUQJ A B C D E F G H I J K L M N O P Q R S T U V W X Y Z V W X Y Z A B C D E F G H I J K L M N O P Q R S T U FQQ using the same code would = all Set UJTUQJ = PEOPLE

Intermediate Decode Try converting FWTZSI A B C D E F G H I J K L M N O P Q R S T U V W X Y Z K L MN O P Q R S T U V W X Y Z A B C D E F G H I J Since it doesn’t match, you know the other is correct

Intermediate Decode Answers Message One UJTUQJ FQQ FWTZSI YMJ BTWQI QNPJ YT XTQAJ UZEEQJX. People All Around The World Like To Solve Puzzles.

Intermediate #2 Message Two MIGY JOTTFYM WUH VY BULX NI MIFPY, VON MIGY ULY YUMS. HINT: The word "SOME" appears twice in this sentence.

Intermediate #2 Message Two MIGY JOTTFYM WUH VY BULX NI MIFPY, VON MIGY ULY YUMS. HINT: The word "SOME" appears twice in this sentence. A B C D E F G H I J K L M N O P Q R S T U V W X Y Z G H I J K L M N O P Q R S T U V W X Y Z A B C D E F Let MIGY= SOME

Intermediate #2 Message Two MIGY JOTTFYM WUH VY BULX NI MIFPY, VON MIGY ULY YUMS. Some Puzzles Can Bb Hard To Solve, But Some Are Easy.

Intermediate #3 Message Three QVQ LBH GUVAX GUNG GUVF CHMMYR JNF UNEQ BE RNFL GB QB?

Intermediate #3 Message Three QVQ LBH GUVAX GUNG GUVF CHMMYR JNF UNEQ BE RNFL GB QB? HINT: Three words in a row begin with "TH."

Intermediate #3 Message Three QVQ LBH GUVAX GUNG GUVF CHMMYR JNF UNEQ BE RNFL GB QB? HINT: Three words in a row begin with "TH.“ A B C D E F G H I J K L M N O P Q R S T U V W X Y Z N O P Q R S T U V W X Y Z A B C D E F G H I J K L M Let GU = TH

Intermediate #3 Message Three QVQ LBH GUVAX GUNG GUVF CHMMYR JNF UNEQ BE RNFL GB QB? Did You Think That This Puzzle Was Hard Or Easy To Do?

Advanced Message 1. LHKUFXKUL, J LXYIRU ETMMRU KJD NU KJQU TE HV LUOUBJR EJBFL. 2. KEON MEGS FCHS IK HBWRKJ QX BGJKG SB OBFK SB E OBFMWKSK HBWCSQBX. 3. VGT OANRV UZNV WO VGAR UFKKBT AR RWBHADX VGT LNQUVWXNZCR VGT CRTBHTR. 4. IMQC XRK TKOC AMCMWTDIM CBM FMXNRWA KOMA CR TDQ CBM PHZBPGMC. 5. TNUJTH, HKA QAUJ ZRLAFX KAJ JCX SKFW AUXW ZKF JCX UXJJROL.

Advanced: Step 1 Decode each sentence LHKUFXKUL, J LXYIRU ETMMRU KJD NU KJQU TE HV LUOUBJR EJBFL. The give away is the letter “J” –what are the only stand alone letters/words in the English language I or A

Advanced: Step 1 Decode each sentence LHKUFXKUL, J LXYIRU ETMMRU KJD NU KJQU TE HV LUOUBJR EJBFL. Set J = I A B C D E F G H I J K L M N O P Q R S T U V W X Y Z Z A B C D E F G H I J K L M N O P Q R S T U V W X Y Pick something to test. For example does TE = SD make sense?

Advanced: Step 1 Decode each sentence LHKUFXKUL, J LXYIRU ETMMRU KJD NU KJQU TE HV LUOUBJR EJBFL. Set J = A A B C D E F G H I J K L M N O P Q R S T U V W X Y Z R S T U V WX Y Z A B C D E F G H I J K L M N O PQ Pick something to test. For example does TE = KV make sense?

Making Interactive PPT and EXCEL Examples of Excel

See Handouts for Directions In Excel Secret Messages Plot the Secret Location See Handouts for Directions Answers: Secret messages Plot the location

Interactive PPT Examples of PPT

Remainder of Time Visit America's Crypto Kids (K-12) National Security Agency (NSA) http://www.nsa.gov/kids/ CIA Kids’ Page (K-12) Central Intelligence Agency (CIA) https://www.cia.gov/kids-page/index.html FBI Kids’ Page Federal Bureau of Investigation (FBI) http://www.fbi.gov/fbikids.htm Future State U.S. Department of States http://www.future.state.gov/ Ready Kids Department of Homeland Security http://www.ready.gov/kids/home.html

http://www.eschoolnews.tv/ http://cryptoclub.math.uic.edu/shiftcipher/shiftcipher.htm